163 thoughts on “Ditching your two strokes carb for Port Fuel Injection”

1. Oh. My. God.

2. The time has come. If the aftermarket puts out something this clean and simple, then the factories will be forced to follow through. Imagine the first Motocross Action test of this system, combined with emissions info from comparative carburetted 2Ts and “diesels” to show cleanliness/noise/power/maintenance/tuning as part of the comparo…

   Either this will show up on factory bikes within two years, or the designer will end up dead in a mysterious hit-and-run pedestrian accident.

3. Excellent news.I do have to disagree with the direct injection comments,DI is the future for two cycle engines and the Skidoo/Rotax powerplants have already demonstrated this.

4. For anyone having as much trouble processing what was being said as I initially did reading this article (I’m not sure who actually wrote all of it, but it’s all over the freaking map and lacking cohesiveness, especially the first section)….this is essentially a F.A.S.T. EZ EFI system for two strokes.

   For those of you who don’t know what I’m talking about, here’s the website:
   http://www.fuelairspark.com/ezefi/default.asp

   If you have never contemplated converting something over to electronic fuel injection, having researched various conversions over the last two or three years….Jesus Christ, whatta minefield. The biggest thing the EFI cheerleaders tout is EFI’s adaptability, yet every system or modification requires someone to tune it….wait, isn’t this what we had to do with a carb?

   My research included attempting to ascertain how ‘easy’ it might be to get various systems to work (primarily the piggy-back systems that work on Fords)….and even the guys who make it can’t seem to speak two coherent sentences in a row when it comes to how a newbie might make it work.

   Screw that.

   If this works with the two-stroke….My God, like the FAST EZ EFI, it’s a thing of beauty. Unlike the 4-stroke variant I listed….if this two-stroke unit works (as advertised)….you can pretty much install it, set it up, and forget about it. The FAST car system does the same thing, but it’s a simple, cut-down version of FAST’s excellent EFI system, which works with almost any 4-stroke car engine, even if it’s equipped with a turbo, blower, nitrous, whatever.

   The EZ EFI does not work with blowers, turbos, or nitrous, nor does it include any spark control.

   However, it’s not what it doesn’t include that’s monumental, it’s what it does do that is wonderful; you’re no longer a slave to ‘tuners’ who plague the automotive community. I have a project car, sitting in the garage, and I was absolutely scared of attempting to modify it, as the nearest ‘tuner’ is at least 200 miles away….meaning if I do any other modifications later, it requires multiple road trips to this guy….if he’s any good. I don’t want a carb, simply due to the elevation and weather changes that are in my area, and the garbage ethanol-laced fuel they sell here. EZ EFI, which I’m seriously considering….I install it, set it up, drive it, make any necessary changes to the hand-held computer….and forget about it. No ‘tuners’ required.

   If this kit does the same thing for bikes….wow.

5. Sorry, it’s got nothing to do with this particular article, but rumor has it that Roczen and Cairoli will be running 125 and 250 two-strokes, respectively, at this weekend’s Italian GP. If the rumor is true, that’s awesome. When’s the last time a *factory* effort fielded, not one, but two pingers? Bravo, KTM. They’ve got their titles wrapped up, so let ‘em have some fun!

6. sounds absolutely amazing!……do i hear fuel injection for project yz144?!?!?!

7. This sounds amazing. I am going to have to look into this for my bike. As long as it doesn’t cost too much. An all-in-one system that is easy to install and tune sounds great. I was considering trying to adapt a 4-stroke injection system onto a 2-stroke but this will be easier and cheaper.

   Although I disagree on “For performance, (Direct Injection) is not the answer.”
   This might be true for the Aprilia RS50, but not DI in general. Not only has DI proven to make more power in 4-stroke cars, but it works in boats and snowmobiles. The Mercury Optimax 2-stroke outboards also use Orbital DI with none of these power problems. Same with Evinrude E-Tec. When Ski-Doo switched their 800 from EFI to DI it made more power with much better emissions.

   EFI can be a great conversion for carb 2-strokes, but it is not a long term solution, nor the best solution. DI can provide as much or more power, better control and most importantly, the emissions to be able to continue selling them and sell them in new markets.

8. Hello Guys

   This is Richard with High Gain Tuning

   I didn’t know this even posted as I thought I would get some time to re-proof it so it is a bit off course. I just received a call that it had by a reader. The artical by all means doesn’t touch on 1% of the capability of our system and it is a ground up design for two strokes.

   I read what Larry said and the primary concern I had when developing this was to make it as easy to install as possible. I determine what ships after knowing what it’s going on so it is not a one size fits all system but pretty darn close as the throttle body and injectors are all that we change out. It comes pre-programmed so you don’t need to even learn the depth of the software unless you want to.

   The software has self intellegence so if you wanted to pull it from a 70cc engine and put it on a 90cc engine you just tell it what cc engine it’s going on and it recallibrates the maps for you.

   Every two stroke I own is running this and we just started releasing it to the public.

   I’ll be happy to answer any questions you may have.

   Here’s a couple videos of engines running this.

   This is a little 65cc Aprilia SR50
   http://youtu.be/LfgTEzrMNIs?hd=1

   This is an Aprilia SR50 we just took to 86cc and shipped to a customer. It’s a CVT but when we Dyno them we use our own lock up system to first find peak HP
   http://www.eventualhabit.com/ScooterPictures/IMG_6801smaller.jpg
   

9. This is the video for the 65cc Aprilia
   

10. Richard this looks great so far but two questions keep popping up in my head, main bearing lubrication, and the final price of the kit. Thanks, Malcolm.

11. Main bearing lubrication stays the same as you are running now..

    If your pre-mixing, keep pre-mixing.
    If you have a pump and the fitting was on the carb, it can now be on the throttle body, manifold etc.

    Price is $995.00 retail through Dealers which I haven’t fully decided on yet. If I choose to sell direct, obviousely less than that but one man can’t support all the tech support which is why I prefer to train some dealers.

12. Richard, as I said previously, I had no idea who had wrote this piece. If you are going to post this info somewhere else, I would make sure to clarify, specifically, why you didn’t go with direct injection initially. From what I can piece together, you don’t have a direct injection kit to sell, correct?

    If correct, I would clearly point out that you don’t have a DI kit, and that the kit you are mentioning is someone else’s system, not yours. This contributed to the initial confusion I was experiencing when reading this initially (and my son’s), as it appeared that you were first selling a DI unit, and then not selling it due to two reasons; it supposedly doesn’t work that well, and the entity that owns it doesn’t want it released to us off-road monkeys, as we would obviously screw it up….that, or we’re facing another ‘withheld technology’ moment, where idiot bike companies seek to fleece us with substandard, overpriced 4-stroke garbage….while hiding the ‘good’ stuff from those who actually want to buy it.

    More later…

13. hello Richard, I think that there are a few thousand readers that would like to know the price. Please, let us know – we all have been waiting for this styuff for wayyyyyy too long:-)

14. Look at the post just above yours

15. Bearing lubrication will remain as it is… If your pre-mixing, continue to do that. If you have a mechanical pump or pulse solenoid that was tapped into a port on the carb, it can be put on the throttle body or in the manifold.

    Cost is $995.00 Retail (70cc-100cc system) through dealers for a turn key system if I go that route. I am still talking this over with a few interested shops. If I sell direct, it will obviously be less but there is no way I can handle the tech support by myself. I am working out the cost on larger throttle bodies, mainly a 40mm for up to 250cc cylinders but the US manufacturer is very proud of them which would add another $300.00 or so to the cost. I do have to say, they are killer throttle bodies though.

    Dealers would need to be doing 2 stroke service already with a strong background in electronics and some knowledge of fuel injection. I prefer they own a Dyno.

16. Would a system be available for a Husqvarna 144 WR offroad motorcycle?

17. Hello Larry

    The pictures I gave twostrokemotocross for the article did not have the picture of the Malossi DI kit which I do sell on my web site. That is a kit for a 2009 and forward Piaggio engine. I have no idea how that picture got into this article and I have contacted both John and Charles regarding this. I agree, it makes the article very confusing; in fact none of the pictures I provided made it into the article.

    I have worked with the Synerject DI system which is an extremely efficient system. Since it injects the fuel after the exhaust port is closed it leaves little to no hydrocarbons to escape out the pipe. You cannot squeeze anywhere near the horse power out of a DI cc to cc as you can a carbureted or non DI fuel injected engine and there are major draw backs to the engine that are not wanted in the motorsport racing industry. My PFI system is not for the OEM’s. It is for the off road racers that want to gain the advantages that fuel injection offers over carburetion which is listed in the article.

    After working with DI for many years, following are the reasons why I made no attempt at doing a DI kit.

    1. For a DI to have adequate time to vaporize the fuel mixture anywhere near a non DI engine the port timings need to be lower than we see on any 2 stroke race cylinder. This will put the peak power band in the 9k range as they are on the Synerject system. The exhaust pipe manufacturers that are here today, do not manufacturer pipes for that power band. We see this already in the DI industry and pipe choices for DiTech’s are few or nonexistent. If this was a DI kit, your current pipe would not function properly with no place to get a correct pipe making a kit virtually useless.

    2. DI requires either an extremely high fuel pressure which requires a high current draw fuel pump or a mechanical pump for non air assisted injection. For a lower fuel pressure (110 psi) air assisted DI design an air assisted system like Aprilia uses on the SR models is needed. Both of these pull HP from the engine and add unwanted side effects. The air assist is of the worse designs as it creates an emulsion of condensing moisture and 2 stroke oil vapor much like what you drain out of an air compressor. This follows the air tract and gets injected into the combustion chamber which is not a combustible mixture and creates misfires. This is the #1 complaint of all Aprilia Ditech owners.

    3. A DI kit requires a DI cylinder head, DI cylinder, fuel pressure regulator, Injection body, DI pipe, DI injectors, ECU etc. and some way to adapt this to an existing 2 stroke engine. Not only is this much work far above what anyone wants to do, they could go out and purchase a new bike for what it would cost. All this for less HP than they had with their carburetor.

    I have been repairing OEM DI two stroke engines for years and they are fuel efficient clean burning oil sipping engines with a good power to cc ratio. If you purchase one as I did you will soon find they are not up to the power you were used to with your carbureted engine. You will next find that there is little to no way to make them stronger and the aftermarket parts available are inexistent.

    A Port fuel injection kit brings all the advantages of fuel injection to your current two stroke as listed in the article above with no need to change your current engine build. Every part that is currently available for you engine today will continue to work with the HGT Port Fuel Injection system.

    I hope this helps because this was not intended to be another DI discussion nor do I have any interest in further investing money or time in DI technology for the aftermarket.

18. Hello SachsGS

    The HGT PFI system has 2 ECU’s available. A CDI system and a transistorized ignition system with any tooth count trigger wheel. The tooth count, missing tooth and position to top dead center is all programmable. With that said, that should take care of all 2 stroke engines that I am aware of.

    The only variable is the size of the throttle body required as said earlier. Since the throttle body has very little to do with the injection of the fuel there are only a few choices needed. Larger throttle bodies do not lean out an engine or change bottom characteristics since the fuel is injected under high pressure in an already very atomized state. Too small of a throttle body will restrict air flow.

    The larger throttle bodies are cosing more to be produced.

19. Would this be suitable (read increase power) on a Honda RS125R roadracing motorcycle? It’s already making around 50 hp with a carb.

    Could you feed the signal from a detonation sensor to the ECU to make the mixture richer when needed? KTM did this in the GPs with a carb having an electronic power valve coupled with a detonation sensor. They got maximum power without destroying the engine.

20. Richard, I was going to comment last night on what it actually costs to put DI onto a bike like this….but I had to stop early. It’s pointless to try to retrofit DI to current motorcycles. From what I’m recalling from the Automotive world, most gasoline DI systems need at least somewhere around 1000 psi, if they’re not air-assisted as you suggest (I’ve read some systems use over 2000 psi). On the four-stroke side, switching to DI does have some advantages, but a major disadvantage is intake valves, which were cleaned continuously by port fuel injection….there have been several instances of intake ports becoming almost completely blocked off with crud, requiring intake manifolds and heads be removed for cleaning….

    The added complexity, in addition, is unnecessary, not to mention hideously expensive. I think what we’re going to have to realize, is that we can’t get our teeth any damn whiter (an Onion article joke), meaning that we’re kind of getting to the end of what can be done with these types of engines, from a efficiency and power standpoint. DI stands to make simple, easy-to-repair-and-tune 2-stroke engines into an overcomplicated mockery of 4-stroke disasters…which kind of defeats the point of two-strokes, doesn’t it?

    This port EFI system is pretty much all we’ll ever need for these bikes. I’m curious to see what it would do on my KDX.

    The true problem we all need to get behind is uncovering what’s behind the ‘we know what you need better than you do’ mantra of the manufacturers….

21. There are too many problems with retrofitting DI to a non-DI engine.
    1) LUBRICATION. Now that your fuel is skipping your bottom end and going straight to the cylinder your pre-mix is useless. DI 2-strokes have oil injectors throughout the engine to solve this.
    2) Cost. In order to get the fuel pumps and high pressure injectors, etc and the cylinder head, porting, piston, etc and the lubrication fix it is more than a new bike, like HGT said.

    I still don’t believe the “they are not up to the power you were used to with your carbureted engine” statement. I will again bring up the Evnirude, Ski-Doo and Mercury engines. When Ski-Doo switched from carb to EFI they gained power. When they switched from EFI to DI they gained more power. While EFI they made 150hp. The DI engines make 160hp. Mercury switched from EFI to DI with no power loss, and they use Air Assist like Aprilia. I think the problem you have seen is Aprilias system, not DI in general.

22. Larry VanZandt, I have to disagree with your comments.
    “DI stands to make simple, easy-to-repair-and-tune 2-stroke engines into an overcomplicated mockery of 4-stroke disasters…which kind of defeats the point of two-strokes, doesn’t it?”
    All the 2-stroke advantages are still there. Same maintenance. But instead of cleaning a carb you clean an injector (~$20) and instead of tuning a carb you do nothing. You DON’T have to tune DI, just like EFI. If it is done correct it is a forget it setup. It changes for elevation automatically.

    “hideously expensive”
    If the overall cost of a 2-stroke dirt bike goes up $500 yet the end result is they continue manufacturing them, we see better bikes, more improvements, green sticker, etc it is worth it.

    “meaning that we’re kind of getting to the end of what can be done with these types of engines, from a efficiency and power standpoint.”
    No no no. Just a NEW set of problems to solve. People thought EFI was going to kill cars or be worse etc. Started out rough but they kill carbs now. People thought it would be impossible to meet emissions standards in cars/boats/snowmobiles/etc yet they all did it. I think the biggest problem with DI cars is not the DI but the fuel. It is hurting older cars more than new cars. Blame the alcohol not the DI.

    “This port EFI system is pretty much all we’ll ever need for these bikes.”
    No way. Not if you want to see future 2-strokes produced. And not if DI can improve on EFI the same way EFI improves on carb. It worked in boats then snowmobiles, without it they would now be extinct and they had no performance loss. Motorcycles are next.

23. Thanks Charles for getting that DiTech pic out of there so we can get back on topic.

    Larry; I’m glad to se were on the same page now. For two stroke single cylinder MX engines, all I need to know is your current carb size and the outside diameter of the carb where it couples to the rubber manifold. I have access to 40mm, 45mm and 48mm throttle bodies which should cover a wide range of cylinder sizes. We do a flange to go from the manifold to the throttle body to make an exact fit.

    I will get some in inventory so we can get some of these out to you guys to test.

24. Hello High Gain Tuning,
    Thanks for the quick reply.Do you have an example of an offroad twostroke motorcycle that has been equipped with one of your systems? Thanks.

25. I don’t now but will have one after the 19th unless you want to be first

26. From what I read its suitable for up to 400cc singles? I was thinking it would add a nice touch for my thirsty CR500.

27. I have received a lot of questions regarding the size of the throttle body for a 250cc and up. I’m having some of these made and I have my own milling machine so I will customize them for twin injection, oil injection ports etc.
    [IMG]http://i53.tinypic.com/1z556h3.jpg[/IMG]

    I am also being asked; “What is staged injection”

    I run dual injectors to get the very best power and lowest emissions through atomization. The first injector is small with around 40 psi of pressure applied to it. It handles cold start-up, idle and all metering until it cannot handle the demand then I bring in a larger second injector and drop the pulse width on the first. The 2 together sharing the overall pulse width can take an engine to 16,000 rpm.

    There is no carburetor that can do this with its 3 circuits. My PFI System has essentially 192 circuits and I can change any one individually or all at once.

    [IMG]http://i56.tinypic.com/2cy5gj.jpg[/IMG]

    Keep the questions coming.

28. Can we see a dyno chart comparing a stock carb engine to that engine with your EFI on it? A 125 MX bike would show the best results probably.

29. Any size engine will show the same results… Torque comes up quicker, at a lower rpm and peaks higher.

    Horse power will come on stronger and peak higher.

    Here’s the 86cc in the video before and after. I am attaching a HP graph and a torque graph seperately so it’s not so confusing to see the 2. The third is the 28mm Dellorto VHST BS Racing carb that was replaced by the 26mm TB

    http://i53.tinypic.com/14sp2m9.jpg
    http://i54.tinypic.com/2w7lnat.jpg
    http://i54.tinypic.com/2w7lnat.jpg

30. Any size engine will show the same results… Torque comes up quicker, at a lower rpm and peaks higher.

    Horse power will come on stronger and peak higher.

    Here’s the 86cc in the video before and after. I am attaching a HP graph and a torque graph seperately so it’s not so confusing to see the 2. The third is the 28mm Dellorto VHST BS Racing carb that was replaced by the 26mm TB

    http://i53.tinypic.com/14sp2m9.jpg
    http://i54.tinypic.com/2w7lnat.jpg
    http://i52.tinypic.com/2ngbdwk.jpg

31. i would just like to commend High Gain Tuning on how much feedback they are giving us…..i love it when the readers get this much attention. excellent work HGT. you guys may have just sold a lot of fuel injection kits!

32. HGT
    looking forward to trying this on a 12 yz 250, what kind of time table are we looking at to get this on sale and to my door? really pumped to give this a try!!! Has any one tried this set up on the MX track, im thinkin this will be a huge step in the right direction to get more 2 strokes on the track.
    thanks
    YZ

33. I have a question regarding current MX charging systems if any.
    Do your MX bikes have a charging coil within the CDI system and a battery?

    When I first designed this we looked at the Quad MX classes and which classes would allow fuel injection. The open classes allow anything as where some of the smaller classes have to race with what they were produced with. Most open class MX quads toss their OEM stator / charging assembly and run an inner rotor race ignition system that has no charging coil therefore no battery either.

    Fuel injection won’t operate without a voltage supply so for them I have put together LiPo battery packs that are very light yet very powerful. They will easily run the fuel injection system which requires just 3 amps, fuel pump and all for several heats. Additional batteries can be charged and ready to go if needed.

    If DI ever makes it into two stroke MX production, IT WILL require a large charging coil and battery, most likely a heavy lead acid battery. There will be no way to modify the ignition system as I can now.

34. The ETEC system is a battery less system that will run just off the Stator.
    Should be the same with a bike.?

35. yzripper

    I am working out a couple issues for the larger engines, the most important being the throttle body. There are so many two strokes out there with just as many different cylinder and carb sizes. Thankfully there doesn’t need to be nearly as many TB sizes but it sure makes life easy if the manifold will accept the throttle body already. I am sure there are several manifold choices out there for every engine to help accommodate this.

    The measurement I am referring to is (A) in this pic
    http://i52.tinypic.com/dn0hax.jpg

    I can’t possibly produce hundreds of different throttle body sizes but I can have several different flanges made to cover a broad range of coupler sizes.
    http://i51.tinypic.com/jj4olf.jpg

    As soon as I see what kind of demand there is for the larger engines I can start making up several different sized flanges.

    Everything else is ready and I don’t want the throttle body to hold things up or add too much more to the cost of the kit

36. @High gain

    Well, might as well go ahead and start taking measurements for CR500′s…

37. HGT
    i know you want measurments but if you would like i have an extra carb off my YZ 250 that i could send to you if you would like?
    thanks!

38. Give me 3 of the most popular manifold sizes to start with. I’ll have some kits on the HGT website early next week.

39. I think we should keep it simple and realise that most MX japanese and KTM 2 strokes carburator diameters for 125 cc to 500 cc bikes are for a Kehin pwk 36 or 38. For Mikuni carburettors the manifold diameter is also the same, as shown on your design upstairs, where A is 46 mm. and B is 63 . So not a big deal and starting with 46/63 standard size would be a good point…

40. Fantastic news, HGT, I am definitely interested in these kits, as Id like to fit them to a variety of machines I have.

    Just a few questions, you have mentioned a battery is utilized to run the high pressure pump and the ecu, i assume the fuel pump used is located after the tank before the throttle (rather than an in tank model).
    Is there likely to be any issues with inconsistent fueling with low fuel levels on bumpy terrain?
    Having retro fitted efi to cars, I know older style tanks without baffles can require intermediate “surge” tanks to prevent it.
    You have mentioned different sized injectors aren’t an issue. With car efi I know too small an injector means maxing the duty cycle, while oversize injectors can cause inconsistent fueling down low.

    I’m sure these are all basics though, just want to get as good as an understanding as possible. If you can detail a bit more on controlling the ignition side that would be good too. Is this just a matter of installing a sensor or would it take some modifications?

41. Mario

    This can’t be correct… “carburator diameters for 125 cc to 500 cc bikes are for a Kehin pwk 36 or 38″

    I would have done 32mm-34mm for a TB on a 125 and an OMG tapered 50mm on the 500cc

42. Bioflex

    The fuel pump is not an in-tank and needs to be low so that there is always plenty of hose filled with fuel above it. The fuel filter just below the bottom of the tank also helps keep a full supply of fuel sitting on the pump inlet.

    I am running 2 injectors that split the total pulse width at the upper RPM band and they can handle a wide range of engine sizes up to 16,000 rpm. What I ship per kit will always be enough for that engine. We have a wide array of injector sizes for different size engines.

    Take a look at this http://youtu.be/jH65qGDB4u0?hd=1

43. As you can see, I port my scoot engines to really rev. That’s a 13,000 stall clutch on there with a variator transmission of course.

    I hope to have this little 50cc Derbi GPR Racing finished this week.

44. Thanks for clearing that up. If the workings of your kits are anything like your customer service, you’ll sell masses of them!

45. Thank you Bioflex

    We had everything together for our race scoot engines but didn’t know of the interest level in MX until John asked if he could post an article, so not having bigger TB’s caught me off gaurd. Early next week I should have some really cool stuff on the web site.

46. Sounds great! Make one for the 2005+ RM250s and I’ll buy as soon as we see one tested successfully on a track, preferably under racing loads.

    When you guys get it on the 144, might be a good idea to alert the 2T heads over at Vital, Transworld, and MXA about the test. Hell, don’t forget about Dirt Bike and Dirt Rider. This is a really big story if it works well on the track.

    The reason I say “on the track” is that this isn’t scooters. Our bikes get slammed hard, sometimes to the ground. Any system you make better be able to deal with that Richard. It won’t go over well if your $1,000 system goes deader than fried chicken the first time your customer lowsides.

47. I can’t wait to see one of these kits on a 250 MX bike. would give me something to save up for this coming year! This tech coupled with KTM’s re-focus on the 2012 two strokes design can only bode well for the two stroke community!

48. “Cost is $995.00 Retail (70cc-100cc system) through dealers for a turn key system if I go that route”

    Is this price realistic for a “turn key system”?

    turn·key
    Adjective: Of or involving the provision of a complete product or service that is ready for immediate use

    so the control unit, the wiring up, the dyno time, the O2 sensor (Im assuming it has one), the fuel rail, fuel pump, the manifold and injectors?

    your surely that’s a couple thousand worth of gear? or is this the bargain of the century?

    I dont mean to sound like a sceptic, but it sounds like by turn key you actually mean just the control unit, which is far from turn key.

49. Mountian Goat

    I totally understand… This system will run upside down indefinitely if I want it to, but I should make sure it shuts off if laid down but it can’t flood and will immediately restart. In AMA road course, the scoot must shut off if the driver leaves the scoot which is why you see the kill switch tethers. A run away MX bike into a crowd or a scoot approaching 100 mph reeks of a lawsuit although throttles can get stuck on carbs too.

50. CRMotard

    Yes, turn key for the 70cc-100cc engines I have been doing now and if your running CDI and tell me the cc of the engine I can ship the kit ready for that size. I have already spent 2 years writing the maps for these engines. When I build a new 70cc or 86cc Malossi race engine now, it fires right up, I check the coolant and ship it.

    No there is no O2 sensor on a performance kit as the O2 is shut down at anything over 80% throttle opening anyway and we don’t putt around with race engines. This is not a closed loop kit. That we reserve for street use.

    Yes, I could try and sell this kit for $3,000.00 like others have tried to do for 4 strokes and be where they are today… sitting on a couple dozen prototype kits that are now collecting dust somewhere. You sound like you have done some research to know that there are ECU’s available in the market today (mainly for 4 strokes) at $1000.00 a box, nothing else, even the harness is extra.

    I am one engineer with a passion for fuel injected two strokes. I don’t have a huge corporation and fancy facility requiring those kind of prices…. Not that I wouldn’t like a bigger space as I am tripping over myself now.

51. I should add, I cannot do the bigger engines (125cc-500cc per cylinder) at $995.00 as the throttle bodies alone are around $300.00 after machining and adding a CNC flange to couple to your existing manifold coupler. My BING throttle bodies for the smaller cc engines are OEM for Aprilia and although are extremely high quality, they are cast which allows for much lower cost.

52. thanks for the replies… sounds like you should sell a few if it works as well as you claim

53. Do you have a bike you want to put a kit on so you can see for yourself?
    If it makes you feel better, you can pay me a couple thousand for the kit.

54. Hi Richard, thenks for all the comments and information. As all this is new to me, used to handle carbs, would like to hear if we will have to place a battery on our dirtbikes since the EFI system running on the MX bikes uses fuel pump without battery. OK, they use pump inside the fuel tank but does it makes any difference? A fuel pump is a fuel pum right? Sorry if my question makes no sense. Most of my doubts were answered above. Good luck and wait for my orders as soon as you make the TB for 250 and 50cc bikes.

55. Yes, this is a hurdle for anything without a charging system.

    What we have been doing for MX Quad’s, Drag Banshee’s and the like that have no battery is first see if there are CDI’s with small charging coil available. If not we can put a small LiPo battery on board with enough reserve capacity to get through a race or through a whole afternoon of racing.

    The LiPo batteries have an enormous current rating and we have literally started engines off the same small battery pack we run a fuel system with… they are amazing.

56. Yes, this is a hurdle for anything without a charging system.

    What we have been doing for MX Quad’s, Drag Banshee’s and the like that have no battery is first see if there are CDI’s with small charging coil available. If not we can put a small LiPo battery on board with enough reserve capacity to get through a race or through a whole afternoon of racing.

    The LiPo batteries have an enormous current rating and we have literally started engines off the same small battery pack we run a fuel system with… they are amazing.

57. How much is it going to cost for a 125 system then? Or a 250?
    How much do the LiPo batteries cost? For some of us that ride longer then that we will need more power. Unless there is a larger battery. You probably won’t have a problem with the off-road/enduro bikes then, they have the CDI’s for lighting. Maybe it would be a good thing for us to price a CDI vs battery. Although some here won’t like the CDI route as they like the light flywheel.

58. Your site is down.

    Running a lipo on a motocrosser? I don’t like the sound of that. Too bad the charging system can’t produce enough juice to run the system. I’ll keep my perfectly working carb for a motoross bike.

    Would a 6S 4000mah last for a 20 minute ride at the local track?

    What fuel pump for a 125cc motocrosser?
    What fuel pump for a 350cc RZ350 and where would the power come from to run it?

59. Carburetor for my CR Honda 125 is a 38. The KTM is either a Kehin 36 or 38. Yamaha is the same. Suzuki also a Kehin PWK 38.
    These are all for 125 cc. For 250 CC. carburettors are still max 38.
    The vintage 500 I am not sure.
    Tx
    Mario

60. 2STROKEREVOLUTION

    The 50cc – 100cc will remain under $1000.

    I am working hard at keeping the larger throttle bodied kits under $1300. The throttle bodies I have coming in can accept multi sized inlet and outlet diameter mounting rings which keeps the grunt of the cost down as one throttle body will fit a very large choice of cylinder sizes.

    To fit the existing manifold and air box, only the adapters will be different.

    Mario

    What is the air box side and manifold side dimensions of the 38? I will have a bunch of those adapters made up.

    One other dimension that will help is the length of the carb from end to end. I can make sure the adapters are long enough to mimic the carb so it is a perfect fit.

61. Need dimensions A,B and C
    http://i52.tinypic.com/dn0hax.jpg

62. Very interesting! I’ll be making a call.

63. The keihin pwk 38-39 is the same dimensions of almost all 125-500cc MX carb setups. If you build a throttle body setup to those dimensions you will have 99% of MX bikes covered.

64. Hello High Gain Tuninng

    I have a 50cc kreidler turns max. 11.000rpm, has now a 28 Dellorto and piston command intake port ,witch a can change to a reedvalve intake.
    There is at this moment no ODP sensor, only the trigger signal from ignigtion.
    At tis moment the normal used rpm area is 8000-10.500 rpm.
    Can you deliver a plug and play indirect injection kit fot this engine.

    Edward

65. A side note: For those of you concerned about throttle-body sizes….if you are concerned about the TB being too big and killing off low-end torque (or shifting it higher up in the rpm range), or at least making the bike a bit boggy at the lower end….EFI doesn’t behave the same way as a carb does in that it does not require at least a decent vacuum signal to draw fuel out of the carb. Therefore, if you are worried about there being too big of a throttle body on there, TB size is not really an issue with EFI. You can pretty much almost run any size TB on there and not have an issue (the EFI computer and fuel injectors determine how much fuel gets into the engine)….unless you’re trying to install something like a 80mm car-sized unit on a 250cc bike, lol.

    In the automotive world, most of the retrofit systems use similar-size TB’s anyway.

66. Thanks Larry

    I have explained that here in a previous post but it doesn’t hurt to reiterate it. Some have experienced HP loss by going too large on 4 stroke auto engines as I am sure their Volumetric Efficiency was dropping off due to leaving the air tract off.

    I will be testing different throttle body and velocity stack lengths on the dyno to increase HP but for MX bikes, everything should be kept as close to OEM as possible so the factory airbox can be used.

67. Ok. I measured my PWK 38 ss wich is actually an OEM from the Kawasaki 250 2006 which was fitted to my Honda CR 125 in Piacenza by Honda Jolly Racing Team, official World Enduro…
    The carb has the same air box/intake Est, dia. dimension as in your drawing attached.
    I send you the spec sheet we used originally to check the chance of using it and fit to my personal bike.
    Now let’s move on :
    1: I know your system operates beautyfully for road racing machines but the main concerns, for dirtbike application, on my technical opinion, are all related to extreme dust, umidity, shock resistance. We need the controller to be housed in a thight box to protect it from all the above.
    2: dirt bikes are to be operated in the most simple way: the fitting of a battery is not as simple as it looks like in a dirt bike, unless you had about 1 kg of wires and all the necessary hardware to protect it in the air box (the only place where you can fit the battery. Now, if you guys go on the honda website (or any of the other Japanese dirt bikes) and study the system they came up with to fix the same problem for the injected 4 stroke, you see they fitted the fuel pump in the tank (ok nothing new…) and the stator is charging a condenser just to start the ECU and the injector with 1 or 2 kick starts only. We need to do the same thing. The battery is out of question, unless you have it fitted stock like in a OEM enduro bike with lights…
    Battery less starting operation. You just need the right stator, condenser and voltage regulator.

68. Carb sizes :
    http://www.carbparts.com/keihin/pwk_jetting_and_dimensions.htm#Dimensions

69. Mario

    I have all your concerns covered.

70. KTM 250SX 2006: PWK 36-S AG FK18

71. I get the impression from the quotes in the article that HGT arrived at a general conclusion about direct injection based on personal experience with a single application of a single type of DI system. I would like parrot what another poster said earlier by referring to Bombardier’s E-Tech, which is cleaner and more powerful than its carburated and TBI predecessors. It should be noted that their system requires neither a battery nor a super-high-pressure fuel system. As I understand it, the pressure boost required to atomize/inject the fuel charge occurs inside the injector, via a device that can be thought of as a tiny high-power subwoofer. Refer to the following link for some interesting reading on the system.

    http://continuouswave.com/whaler/reference/IAME44-1_e-tec.pdf

    The proof is in the pudding – Though the Orbital air-assist approach may have fallen flat for the Aprilia 50, Bombardier has achieved improvements in emissions, fuel economy and specific power with DI.

    By no means do I mean to disparage the HGT 2T EFI system, though. It looks to be the first real, attainable evolutionary next-step for us two-stroke aficionados, and I, for one, can’t wait to order one for my 07 YZ250. Kudos to the folks at HGT for their work and enthusiasm!

    Jason

72. Thanks Jason

    There are better DI systems and there will continue to be better DI systems but one thing will remain the same… Lack of upgrading.

    Now I have never looked, but I will bet out of the DI systems that are out there today for whatever… the answer to the following questions is few to none.

    How many of them can you alter yourself for better performance?
    How many performance accessories are there for them as compared to carbureted or EFI 2 strokes?
    How capable are owners going to be at servicing them and doing upgrades themselves?
    Do the manufacturers (after passing stringent emissions testing) let you change anything?

    I have found out the hard way, you really want to screw up the way a DiTech runs, start changing the port timing… something we have all become accustom to on our 2 stroke cylinders.

    What fun is racing if everyone gets the exact same bike? Reminds me of the old IROC racing series… look what happened to that.

73. You make a good point. As a rider of limited experience and skill, tweaking for performance is one angle I hadn’t considered. My 250 has plenty of power for me, so I haven’t considered having the port timing changed. My perspective is admittedly narrow – I just want a two stroke that is always running a stoichiometric mix at any elevation and any weather condition without me having to change brass. Both FI and DI would provide that. I do believe DI would deliver more economy and lower emissions, along the way, but let’s face it, gas is cheap and those of us who ride smokers are not losing sleep over the infinitesimal amount of unburnt hydrocarbons we pass through the tailpipe. I suppose I just need to ride more so I can get good enough to keep it on the pipe all the time. That’ll make it run clean!
    Thanks for your involvement in this discussion. Now get back to work on those large-bore kits!

    Cheers,
    Jason

74. “Gas is cheap”
    Where do you live?? LOL

75. This is what the basic kit will look like…. Sorry for the Garage floor photo but I was just starting to layout what I will be including and decided to take a pic. I will get some better photo’s together soon.

    http://i53.tinypic.com/23ticm9.jpg

76. Kit looks awesome! How has the fitting to a dirt bike been going? Looking forward to seeing how that goes

77. I have always been a huge proponent of 2-stroke fuel injection & have to give major props to HGT for developing this product. The excitement generated by Charles’s article was to be expected — we all knew that. However, some of the prices being bandied about for this kit leave major cause for concern regarding the HGT Business/Marketing plan.

    Let me backtrack a little; I ride a 2010 300XC. Much of my riding is close to sea level — my bike runs great with the default JD Jet Kit recommended settings.
    When I decide to head into the mountains (5000 – 8500ft range), I simply swap in a different main jet & needle per the JD Jet Kit suggested settings — my bike runs great.
    When I return home I undo the mountain settings.

    Of course all of you have done the same thing at some point or another.

    My concern is simple; how much money would the riding masses pay to avoid the above scenario? I’m not hating here, because I’m a big fan of what HGT has done. But seriously now, I could easily pay the projected $1300 – $1500 it would cost to switch my 300XC over to FI but frankly I haven’t given it much thought because it’s not even on my “must have” purchases radar.

    Over the last week or so I have spoken to as many riders as possible regarding this article & the HGT FI units. I have yet to hear a single person show genuine interest to purchase after I tell them of the projected cost.

    All I hear is:

    “…why would I do that when I can easily re-jet for free?”

    or

    “A grand?! Are you joking?!”

    How many riders are going to fork over that kind of cash to “refresh” their aging 2-stroke? Hell, at $1,500 the kit is more expensive than many bikes I see on the trails. And there’s the rub; notice that I said “more expensive” and not “worth more”?

    I’m not saying the price is out of line from a cost/margin perspective, because I truly believe the intentions of HGT are genuine — making a sought after product and bringing it to market at a fair profit. However, after all the hoopla has settled I think many of you will plain agree that the proposed HGT kit for dirtbikes is a rather expensive, unproven, and likely complicated “solution” to a problem many don’t believe even exists.

    The simple fact of the matter is this; ~$1,500 to convert a 2-stroke dirt bike to FI reeks of a great product burdened with an ill-planned marketing plan.

    I hope I’m wrong.

78. I doubt there will be any problem selling this kit. 1300$ is very fair especially if it even gets close to a 10% power gain. To me jetting has very little effect on the desire I would have for this kit. The improved power curve and over all gain could really make a 2 stroke even more rider friendly.

79. Hey there, Motorambler,

    What you’re seeing here is not a mass-production price, but the burden carried by any early-adopter in any breakthrough technology. Remember how much 52-inch, 1080P HD screens cost five years ago? The profit margins supplied by those early-adopter/innovator-class consumers allowed the market to get to where it is now.

    Proof of benefit at this production scale and price-point will likely lead to a manufacturer (is KTM listening?) adopting the technology at a much more efficient production quantity. However, if too few are willing to cough it up in the “early-adopter” phase of the technology, it will never be seen enough in the open market (a.k.a.: magazine shootouts/reviews, racing, etc…) to allow a breakthrough to mass production.

    The cost of throttle bodies, processors and injector circuits is already being considered for “diesel” motocross bikes…just give it time.

    As for those who would say “why would I do that when…” those are the classic late-adopters in any technology life cycle…likely the same people who didn’t believe the benefits of liquid cooling on race bikes was worth the complexity and damage potential 25 years ago.

80. A guy could view this from two other perspectives – first,as a hands on way of learning the intricacies of two stroke FI (it’s coming) and,secondly,a used Husqvarna WR125 + 144 kit + HGT FI kit would still probably be less then the cost of a new WR125.

81. Motorambler

    Dingerjunkie has made a very good point regarding start-up cost. With that said, I have no Business / Marketing plan for this. I developed this for my own personal use and through that, many two stroke owners have asked if I would make them a setup. I have built many PFI engines and delivered them with this system throughout this year… all custom from the ground up and every owner elated with the results. Did I design this for the woods racer market… No. Will I be heart broke if I never sell a single system for a woods racer… Absolutely not.

    This article on TwoStrokeMotocross.com started when I contacted John Nicholas after reading a write-up he did on a two stroke Banshee someone put fuel injection on. I was trying to find that person to see what they used for a throttle body since everything I was finding was very expensive. John gave me the name of the builder and after contacting him, I learned it was a one off build that cost him well over $2000.00 to convert to fuel injection…. $1000.00 for the ECU alone.

    I would like to point out, I have not told anyone this system costs upwards of $1500 as you posted so I would appreciate it if you would refrain from posting or telling others that.

    If someone wants to source their own throttle body, I can sell them everything else for $900.00 but “your results may vary”. I have complete kits with 26mm BING (OEM for Aprilia) throttle bodies for $995.00 that will fuel any two stroke up to 100cc to 16,000 rpm.

    Yeah, $1300 will get you a complete kit for any single cylinder two stroke MX Bike up to 500cc. So why the $300.00 jump…. The “Drop In Place” throttle body. Call Kevin at Extrudabody 509-498-8555 http://www.extrudabody.com and ask him why he charges what he does for them. Add to that the machining necessary on my end to add the second injector, shorten the length to an overall 91mm and add the billet CNC 63mm air box flange and 46mm manifold flange so it drops right in place of a Keihin 38mm carb for your MX Bike needs.

    Now if this were any other 2 stroke engine that doesn’t require an exact “91mm” fit to the OEM air box and can use an array of aftermarket filters or can be mounted directly to a manifold you could knock off another $100.00 – $150.00

    Now, with the cost cleared up, you have completely missed the advantage of Port Fuel Injection over an antiquated carburetor (calibrated Drip). May I suggest you go back and read the advantages posted by John in the first article.

    I didn’t develop this just so you wouldn’t have to re-jet your carb for a single change from your current elevation to a favorite higher elevation riding spot. You’re at least aware the barometric pressure sensor will instruct the ECU to do that for you but if you wanted to do a (electronic) jet change you could do that “twice” in about 96 seconds. http://youtu.be/b0CK24D6hnQ?hd=1

    If your only hurdle in owning a carbureted woods racer is re-jetting, by all means stick with what you have and spend the money on a good helmet.

    In opposite light, I want to thank everyone that has posted or called me personally and asked what they can do to help with this project or just put their name on the list to get a kit. The “positive” support has been outstanding.

82. HGT welcome to life on earth.
    If you are smart and successful in this life… you gonna have a lot of haters, hating on you that they were not the first ones to come up with all this.

83. Hey there HGT,

    My post was not written with malicious undertones, and I apologize if it came across that way. I was simply expressing my thoughts.

    I repeat — I fully support what you’re doing and think it’s fantastic that the aftermarket has beat the oems in bringing FI to the 2-stroke. I never questioned your ethics by saying you’re over-charging for the product, either. Hell, I’m sure you’re working with skinny margins to keep the kits as affordable as possible.

    I just think at $1,300 it’s going to be a tough sell to the over 100cc crowd. And once again, I’ll say that I hope I’m wrong.

84. Apparently, I’m getting a new YZ250 on Tuesday.

    I’m not sure why.

    Something about “turning 16″.

    Anyway, I guess that’s supporting two strokes.

    Hurry up with the DI.

    I want it.

85. Awesome kit there HGT,

    I just got a few Q’s

    How water proof is it? like the throttle body and ECU.
    The weight?
    Is the injector in the throttle body and is it timed with the engeine’s cycle?
    I guess the kit would go from one bike to another with out too much hassle?

    looking at one for my YZ 144

    Cheers
    Scott

86. Another vote from the “FI for 500′s” corner. I love my AF KX bur I’m still getting the jetting sorted.
    I could spend the hours jetting for each weather change blah blah blah, but like most peole I know, there’s barely enough hours in the day to even perform basic maintenance let alone doodle with jetting. Kids, wife, work, and a whole lot of other stuff means that I just don’t have the time.
    Sell me a kit at a reasonable cost that will give me a clean running K5 each and every day of the year regardless of weather and altitude, and that’s one more job I don’t have on my list.
    This IS the way to go.

87. Scottydog

    Very waterproof. Initial design was for the MX quad racers.
    Yes, the injector(s) are in the throttle body and timed to piston location.
    You could move it from engine to engine pretty easily. When I started doing testing the same harness was moved around a lot.

88. First off I’d like to say High Gain Tuning has awesome customer support. Just the fact that Richard is responding to all these questions everyday for a system that he’s not even really marketing is great. I sent him an email inquiring about fitting this to my Gas Gas 300EC and got a reply the same day.
    @ Motorambler… Not all of us have life so simple where we can just re-jet depending on where we are going to ride that day. Like what was posted before, I barely have time to wash my bike let alone try and guess what the weather is going to be like next weekend when I ride so that I can get my jetting right. As it is now, I just leave the jetting and live with the crappy low or high end performance that I get that particular day.
    I spent $600 on a steering damper to make riding easier. I spent $300 on a new pipe TWICE because I keep crushing them. $1300 for a FI system where I can ride with a 2000′ elevation change or a 50 degree F temperature change without any performance loss is a luxury I can afford.
    Some guys like the whole ‘tuning’ and racing thing…I only like the racing. If I could afford a mechanic to tune and fix my bike, I would have one.
    As long as this system can stand up to the vibration and hard jarring of the bike being dropped, I’ll buy one. Besides, I bought the Gas Gas to be different than all the other Pumpkin lemmings. Now half the field is filled with Gassers and having a FI one will set me apart again.

89. Richard, please keep us updated on how it goes. Good or bad news, people here will help. We 2-strokers hang together.

90. Motoscrambler,

    I understand you support the product ,and just voicing concerns.
    I can relate and certainly understand them ,
    especially since I operate in a similar high cost, low production niche market.

    I’m also just tossing out opinion—
    I feel this proposed product ,at this price ,does have a market,
    while the market size is yet to be seen,
    the price is quite fair.

    As example: we could offer our 500AF’s in either a carburated version
    or an FI version.
    (the FI would obviously incur a bit more retail costs)
    Honda did similarly with the CBR600 years ago

    As a retrofit kit it also has advantages some will be willing to pay for..
    The average enthusiast, perhaps yes perhaps no..
    as *he* doesn’t always buy a given set of bars or other upgrade goodies either.
    I would view this product along the lines of the auto clutches, which do
    quite well.Many average enthusiast won’t spend their cash on that, yet
    many will purchase them for the improved performance.

    HGT ‘s perhaps is operatng under the :

    *Build it and they will come….*

    I can relate, and wish them great success!!!

91. UPDATE:

    My flanges are to ship Tuesday which makes this a drop in for the Keihin 36mm, 38mm, 39mm carbed bikes…. 91mm long, 63mm air box fitting and 46mm manifold fitting.

    Besides the builds I normally do day in and day out to PFI I have the following coming in for builds so I can get them to a plug and play state.

    RZ350
    YZ 144
    500AF
    Banshee

    This should make for a well rounded group of plug and play systems. Although I am still making these as easy to install as possible for each individual model, I am still searching for Dealers to specifically market and install the kits for their specific needs.

    Stay tuned… I will show the progress of the builds somewhere.

92. Something to consider

    Having a dealer network is adding cost to the consumer. Middlemen need their profit margin.

    If you have this set up as well as I think you could, with Very good setting up instructions, and internet interfacing for customers, you should have no need of ‘dealers’. The world is changing rapidly on this front, and dealers will only add cost.

    The sort of people that will take in this kit, will inevitably be a bit above the average drongo, and will be able to accept that they WILL have to do some adjusting, thinking. We already have to do that with carbs / jetting.

    Provide easy access back up, that can be had through the internet, and you’ll keep the price down, AND be able to have more margin for YOURSELF.

    If you recall my Email to you whilst I was travelling in France, you’ve seen how easy it is to make a body to fit the Vast majority of 2 strokes. Keep in mind also, we are Not talking about engines that deal in any kind of high revs, especially compared to modern 4ts. 125s, you could say an average of 10 /11k max, 250 /300s, 9 / 10k, 500s, 6 to 8k. This is Dirt use, with, especially in the 250 and up sizes, use of ALL the rev range, especially Off Road. Don’t get overly distracted by blokes wanting set ups for rare applications.For example, the bloke with a 500 claiming he’s using a 10K rev range.

    Something that another fellow wrote on another site, is for people to consider that, within your pricing, you get, what I would assume is, a multi adjustable (hopefully with the inclusion of handlebar switches, for multi set up options)CDI that hopefully, is far above a std Ignition set up. If that is the case, emphasize that in your promotion material, as high end ignitions can be 1/2 the price of your whole set up – when you look at it from that point of veiw, it makes the EFI part of the whole thing, remarkably affordable.

    Brilliant effort – I really hope you do well with this, and I eagerly await real world reports on your system – but don’t push the price up / reduce your potential earnings by adopting a near outmoded marketing / supply model, in putting middlemen in place, that are not needed.

    Bear

93. read thru this whole article + comments too. Been ridin smokers for years and of the 8 bikes in my garage 4 are smokers (2 x 250 + 1 x 300 + 1 x 500). gotta agree with whoever commented on the prices. I would consider doing 1 of the bikes for maybe $300 – $400 just to fool around with new kit (who doesn’t love new toys?!) but would not dream of spending more than that just for fun since all my smokers run great here in the desert or in the mtns of colorado with a simple jet change.

    still a cool piece of kit and good luck to htg.

    The rest of you should learn to jet your bikes

94. Agree with ” Bear ” would start out like that too.

    @ thumper ape,i understand your view too but for 2stroke owners who like to fiddle with their bikes like swapping out exhausts every trackday and then its sometimes a pain to jet spot on,easy to get lost in the thin line between pilot air jets & main air jets,powerjets V-twins ect..then a piece kit like this is priceless.

    Really like it,hope this will still be on the market when i saved the cash
    Keep us updated!

95. Thanks for the input guys…

96. Motorambler says: “I hope i’m wrong”. Yup, you are:http://www.ecotrons.com/400cc_to_800cc_Engine_EFI_kit.html

97. Richard, I know a guy who rides a 73 Kawasaki H2 750 triple that is a nightmare to tune. How could your system be fitted to that? Triple TBs?

    (PS: Richard, the dyno charts you have posted on your site need some explanation of what they’re showing. They’re mostly just squiggly lines with no explanation.)

98. I used to have a 750 triple… Sold an RD400 to trade up but shortly after sold it back to the family I purchased it from…. I didn’t find it hard to tune.

    Yes, it would be best to run triple TB’s mated together on one shaft with one tps.

    Yeah, the 09 Piaggio charts would be difficult to follow without knowing the background of the build.

99. Project YZ144 will be starting soon.
    http://i52.tinypic.com/dp96k4.jpg

100. thumper ape
     You miss like 80% of the benefits of this kit.
     1) Easier then jetting changes. No pulling your carb apart every time you ride at a different spot.
     2) MORE POWER. 10% more peak power then your best carb jetting.
     3) MORE TORQUE. More low end torque. This means a faster bike, and more lugging power for technical trails.
     4) Automatic ELEVATION change. Many of us, me included, ride trails in the mountains. I have ridden from 1000ft up to 7000ft, on one trail ride. I really don’t feel like having to make jetting changes 3-4 times on one trail. With EFI I don’t have to.
     5) Increased fuel economy. My minimum ride is 50 miles. I average 65+. Any extra economy is helpful. I noticed my bike has no difference in economy whether I am pinning it or trying to conserve. I bet this kit would fix that.
     6) No flooding. 2-strokes are already better than 4-strokes at starting, and this continues that without flooding.

101. thumper ape
     It gives you the peak power increase of a $340 exhaust setup, the bottom end and throttle response of a $150 reed kit, the clean running of 5 jetting kits, and automatic elevation adjustment and fuel economy that nothing else can give you.

102. High Gain Tuning
     I am looking for all the updates to those builds. That is really a wide range of builds, I couldn’t have asked for a more perfect line up. You should keep an ongoing build log for each one on your blog. Pictures and descriptions, show us how the kit goes on. And the before and after dyno results.

103. @ 2strokerevolution I’m not sure we’re even in the same discussion because you missed the part where I said all my smokers run great at home or in the mtns with a simple jet change (thank you JD Jet).

     Let’s take my CR500. I could buy:

     1: the HGT kit

     Or

     2: an auto clutch, left hand brake, steering stabilizer, skid plate, bark busters, new rubber, and brake pads to last an entire year

     The $495 system someone linked above makes way more sense from a farkles/upgrade perspective however I did not really spend much time looking at it so I can’t vouch for the product.

     Look, even the <100cc kit costs a freaking GRAND! Who rides dirt bikes under 100cc? Kids, that's who! How many peeps are gonna spend a $1000 on their kids bike so they no longer have to jet their 12 year old's YZ85?

     C'mon man, think it through.

104. Its not about jetting. Its about power delivery. FI can deliver all over the place. Carbs work great but they can’t deliver across the curve the same way fuel injection does. Any gain at the peak is a bonus. I run a 295 as it is and I would be very excited to let something like this feed it. To me its worth the money. I’m sure there are plenty of others who feel the same way.

105. Thumper Ape

     As I have said previously, I did not build this system for dirt or MX bikes in mind, but with that said, what should I do with the dozens of requests for an MX Bike kit? Not fill the orders?

     I was asked by John Nicholas if it was ok to post an article here regarding my system and without thought, I said sure, why not. To your surprise, the system was primary built for MX Quad racers… yeah, KIDS!! The under 100cc crowd is enormous. I spoke with many parents, racers and teams at the Indy show this year and could have sold the kits if they had been ready to hundreds of dad’s.

     If you think the only advantage to my system is that you will never have to jet or re-jet again, you are seriously missing the point. That is but one of many advantages. I don’t know that I have even mentioned that dad’s can wirelessly monitor all the conditions of the engine while their child is running it through its paces. No more… how was it running needs to be asked of a 9 year old. They can either record it for later play back or watch it live and know exactly what was going on for later tuning. To aid in setting up their automatic transmissions we can install rotation sensors on the variator, clutch bell and output shaft to show if or when they are slipping.

     Many times the quad will tip over or even flip to never restart again from flooding. This system cannot flood… one kick and it’s started again.

     Just 500 RPM out of the peak power-band and their 18HP engine is now putting out 9HP. These kids run WOT and don’t even let off for jumps. I can set the ECU to pull back the RPM’s so there is no over-rev.

     Regarding your: ” C’mon man, think it through” There is nothing to think through… If this is not for you, it’s not for you. Don’t get your blood pressure all out of wack reading about it and just ignore this article.

106. Here’s a sub 100cc build I am now finishing. Malossi Replica SR50. It came in at 49cc putting out 3.57HP. This is the premier 49cc scooter sold in the US, Aprilia SR50. In a good economy they bring full retail and are about $4000.00 OTD. It will leave at 86cc with HGT PFI putting out over 20HP. This build is already over $12,000.00 I just finished a similar build more for street use at 18.5HP, see dyno comparison below.

     Before: http://i55.tinypic.com/24pf8mg.jpg
     After: http://i56.tinypic.com/zygc9z.jpg
     Dyno Comparison: http://i51.tinypic.com/727×34.jpg

107. I have a 09 ktm 250xcw &before i took it out for very first time I removed the battery, the stator/electric startre, the headlight all wiring, etc. I have buried it in bogs deep enough to swim in. I drag it out, pull the filter, pull the plug, turn it upside down, pump her stomach, slap it back together & she fires up the first time.

     Iride smokers for the same reason that many others do; theyre simple. I dotn have any software engieneers to ride with.

108. You guys with your fancy complicated gas engines! I’m going back to steam power!

109. woods rider
     You just don’t get it do you?
     Why not get rid of your powervalves, reed valves, ignition advance, long travel suspension, disk brakes, hydraulic clutch, powerful Brembo brakes etc.? Oh you want your reliable, clean running, smooth, powerful 2-stroke/dirt bike?
     Sorry, but times change and technology advances. This is one of those areas. More power, more low end torque, no jetting problems, no bogging, no flooding, etc. And if you read the article, NO SOFTWARE ENGINEERS NEEDED.

110. thumper ape
     Did you read half my comment?
     1) 10% more peak power: your best jetting can’t do that. Neither can the auto clutch or left hand brake(both useless imo)
     2) Power delivery. Want your bike to run amazing in mid range? You are going to have to give up some peak. Want peak? You are going to have to give up some low-mid. EFI boosts BOTH.
     3) Increased fuel economy. Nothing you listed does that.
     4) Auto elevation compensation. Jet your bike for 1000 ft and by the time you are at 7000ft you have lost considerable power. EFI automatically adapts. Do you really stop in mid ride to pull your carb apart to re-jet? Too much hassle.

     This kit might not be the best first mod. Yes, other products can give you some similar effects for cheaper. But imagine a bike ported AND EFI. You will have the best running enduro on the mountains.

     About those <100cc's. LOTS of kids race 85s. Those bikes can use all the power they can get, especially in the low end. If your kid races this kit can give him/her a significant advantage.

111. thumper ape
     This technology might not be for you. If you don’t need more power or you don’t ride trails with big elevation changes then it may not benefit you enough to be worth it. But for a lot of people it is. Those that need the extra performance to hang with the 450s, those that want extra torque for enduro, those that want extra gas mileage for long rides, and those that want to be on the forefront of technology. Remember, this is the type of technology that is going to keep 2-strokes alive. All new tech is expensive, and this is new to 2-strokes.

112. Hey man I love my smokers as much as the next guy. In fact, my 4 stroke pigs do nothin but gather dust in the garage – I’m just too lazy to go thru the hassle of sellin ‘em. I will never buy another 4 stroke enduro bike cuz they are too heavy, too complicated/expensive to fix, and they just can’t take extended abuse like a smoker..

     And I’m all about making sure the 2stroke survives well into the future.

     My “problem” is this: I’m not stupid with my money

     Having said that, can anyone comment on the $395 Ecotrons kit? I’m away from my pc and websurfing on my phone sucks.

113. The machine shop is now saying next Thursday before they have an opening to do the flanges. The drawings are done and there just sitting there waiting to be milled around their racing schedule. I have had this same issue for two years now in everything I have been getting machined. We have plenty of local machine shops within a mile of us and they are so slow they are working 4 day work weeks and laying off employees.

     Here I am try to keep everything in the Good Ol USA and if I take CAD files over to them and say I need 25 of XXX, they laugh while you see employees clocking out because there’s no work.

     Oh well… I have plenty of other work that needs to be done but was really wanting to get the YZ 144 build started.

     Any CNC shops out there that want some business?

114. HighGainTuning, I’ve got three questions I’d like to ask you.

     1. Have you got any real dyno results (not expected curves) showing the change from carb to FI (without the bore, pipe, etc, as the ones you’ve posted before).

     2. When will you have available results from the YZ144 to show us (i.e. dynamometer results)?

     3. What is the tuning/calibrating method? I don’t think you’ve explained too much on this but from I’ve read you’ve simply said you introduce the engine displacement to get a baseline and then it calibrates automatically? How is this? Has it got a Lambda (oxygen) sensor incorporated, or an EGT probe? Please expand on this as it’s one of the base elements that needs some more explaining.

     Thanks in advance,
     Max

115. Hello Max

     I don’t quite understand your first question. I have many Dyno runs with my PFI system as previously posted but nothing as of yet for an MX bike if that’s what your asking. This is a real dyno comparison made on the Dynojet SD12. http://i53.tinypic.com/14sp2m9.jpg

     The YZ 144 project is just the engine… If the whole bike was shipped, I could have done before and afters.

     I just received the YZ144 last week and the flanges for the TB’s are now delayed until late next week. That is the current hold up. Even after that is done, I don’t have a way to Dyno just an engine so maybe TSM had some done before.

     I don’t want there to be much of a tuning method for the end user which is why I am trying to acquire engines to map. I want these to be as plug and play as possible. I bill at $75.00 an hour and can easily put in 40 hours mapping and Dyno tuning a new engine. To this point, I have been eating all that cost. After mapping here for a specific engine, the baro sensor should make any adjustments needed for elevation changes. Of course if the end user wants to make adjustments the software will fully allow that in either global adjustments or a cell at a time.

     No, The High Performance system does not ship with an O2 sensor… O2 sensors do not tolerate oil.

     I am working on EGT feed back now which for a two stroke would be awesome but also more expensive.

116. first off i think alot of you are looking at this the wrong way this is not just a way for you to be lazy an not bother jetting your bike for everywhere you go and no im not slatin people who do this, however this is not just to save rejets but instead for the people who are trying to race the current 250 two strokes against a field of 450fs on an average budget (jeremy welkenden springs to mind as one of them but there are thousands more) and wheen you consider a YZF 450 in the uk retails for around £7500 and a KTM SX 250 retails around £4500 that leaves £3000 thats THREE THOUSAND POUNDS that you saved straight away that you can spend on mods for your new two stroke before you even get to the work you probably would have had done anyway to that 450 those 3 thousand pounds could easily pay for the HGT FI kit along with a suspension revalve, a pipe, a set of triple clamps new tyres and maybe even a full engine tune up and some custom graphics to match now thats a pretty damn cool 250 right? all for the same price you could of ended up paying for a standard YZF
     so while spending an extra grand on efi for a new bike might seem a lot its still less than what the manufacturers charge for it on the fourstroke with the old technology thats decades old

117. Great news. Will be interesting to see how the aftermarket adapts when the oems start offering their own kits. I’ll be in for a couple kits but only when they’re priced more sensibly (i.e., below $500 for adult size dirtbikes).

     Cheers,

     MM

118. HighGainTuning,

     How much current does the kit draw, and what size battery are you looking at running?

     Thanks
     Scott

119. Scottydog

     A single cylinder system draws just under 5 amps peak. A good quality 5000 mAh LiPo battery would run a vehicle a good hour with no charging system at all.

120. HGT, good luck with your YZ144 project… has me wondering if the DI injector is up to the task of providing enough fuel @ 12000 RPM or so where a 125 peaks, could lead to the need of dual alternate firing injectors. May I ask along which fuel pressure ranges are you working ?

121. @Francisco

     “The ECU offerings are compact in size and easy to install supporting two-stroke displacements from 40cc to 400cc per cylinder. Current production supports twins up to 800cc. Triples and custom four cylinder engines can easily be accommodated with additional drivers. The HGT PFI System can support engines spinning up to 16,000 rpm via a staged dual injection strategy.”

122. Well, my credit card was ran so that means parts are being machined finally… This is a Race Car shop (drifting) that has the equipment to do the job but on their schedule.

     Seriously, If anyone here owns or works at a CNC shop that wants some work, please contact me.

     I was really hoping to have this started before other projects started arriving. Now i’m buried with half a dozen different PFI builds…. it’s finally fall everywhere.

123. Look what I got in today… Enough for 25 bikes.

     46mm manifold coupler and 63mm air box coupler.

     http://i56.tinypic.com/2mez3ig.jpg
     http://i52.tinypic.com/wipstu.jpg
     http://i55.tinypic.com/28tl6jn.jpg

124. Howzit there. Any progress on teh Yz 125 project?
     Any new feedback from testing, generator… etc.?
     Ciao

     Mario

125. Mario

     I am re-designing the Throttle bodies to be a direct drop in with exact 36mm-39mm Keihin specs. I should have the dual injector holes finished today

     http://i43.tinypic.com/2e5i43k.jpg
     http://i44.tinypic.com/w89aaf.jpg
     http://i43.tinypic.com/245ehd1.jpg

126. Something I think HGT is change what they call this type of EFI. Port Fuel Injection is confusing, and in my opinion, inaccurate. It should be called throttle body injection. In a car TBI was exactly what this is, replacing the carb and throwing an injector in its place. Port fuel injection in a car is where it shoots at the valves, almost directly into the cylinder. I would consider the Ossa (trials) system port injection as it injects into the crank. The Ossa enduro is more like semi direct injection.

127. Fuel injection SAE J1930 definitions:

     EFI: Electronic fuel injection. Generic for all electronic fuel injection systems

     TBI: Throttle body injection: All Injection is above the butterfly valve using 1 or more injectors.

     PFI: Port Fuel Injection: Injection is after the butterfly valve but before the combustion chamber. Injectors are usually placed in the intake manifold tract.

     DI: Direct Injection. Injection is directly into the combustion chamber.

     Ossa is a mix of DI and PFI. One injector in the cylinder and one in the crankcase. DI will give them very good emissions cable of passing current European and US emission standards. DI will not give them the performance which is why a secondary injector is in the crankcase. If they activate that injector above 80% throttle opening, it is excluded from emission testing as anything above is considered WOT and the government does not test at WOT.

     Smart move but it will need to remain as purchases with few to no performance options ever becoming available.

128. Em 2-STROKES

     twice as quick, twice as powerful, twice as much fun!

     of course a 4 stroke isnt going to out do a 2 stroke. once manafactures clean there act literally well be haveing fun again. i feel sorry for people spending thousands on a four stroke 125 when a 50 2 stroke is embarasing them!

     halleluyah for DI cant wait to buy a kit for my rd 350 or rz 350 depending were you are in the world.

     Its better for the enviroment half the size engine for same power of twice the size 4 stroke, unless your going to get a 4 stroke reving at 20,000 rpm! ha.

     less weight, smaller engine, less parts, eaisier to maintain!

     so 2 strokes will be around for ever.

     now with DI and all that micro chip stuff cant wait to turbo or supercharge as well!

     help the world and carbon foot print buy perfecting the emissions of the 2 stoke !!

     baggey

129. I’ve read thru this whole write up, great stuff! Very tempted to do this on my current kx500AF project now. Richard, please keep posting pictures when you get something from the machine shop, thats awesome eye candy.
     One question i do have is concerning the battery power system. LiPo batterys are very impact resistant and resilient, but i’ve got several friends in the RC car hobby and most every one has had a LiPo malfunction.
     a high quality 5000mAh battery will run around 80-100$, weigh around 12oz, and need a somewhat expensive LiPo specific charger. I just see this being a bit of a crutch, to have a pretty reliable system (yours), then coupling it with something that could possibly at any time make it unusable. and 5000mAh will only provide around and hr of ride time you said? thats a lot of battery changes/charges
     this is in no way a negative remark to your product, i’d just love some clarification on what other options there are to not have to worry about these issues.
     thanks!

130. While shortening the TB to be an exact Keihin 39mm replacement I finished the dual injector unit good to 500cc @ 8500 RPM or 630cc @ 6800 RPM

     http://i39.tinypic.com/ztvv6.jpg

131. JBernard

     Well… I do all the proto-type work and it sure doesn’t start out as eye candy.

     http://i44.tinypic.com/14brk00.jpg
     http://i44.tinypic.com/2d5945.jpg

     It does looks nice after about 16 hours of machining a one off + the time I put into the CAD drawing for mass production.

     Regarding power, the LiPo is only for a system with no charging coil and that is a small percentage of my requests. MX 2 wheel and 4 wheel racers could easily run an afternoon of heat racing with 1 5000mAh pack. I prefer a small charging system with a small AGM battery. Many battery manufacturers, even some I cannot find on the net have contacted me about supplying a battery for my needs so I am entertaining possibilities.

132. I am curious if this system can help with a couple of classic two stroke problem areas.

     1. Two strokes dump a lot of fuel out the pipe reducing their mileage. Now I realize this isn’t a DI system that can squirt the fuel in after the exhaust port is covered but could improvements in mileage be made by injecting the fuel as late as possible in the cycle, so at least less of it was pushed out the exhaust port? Even if it wasn’t possible at WOT maybe it would make a noticable difference to trail riders when they are just cruising. It sure would be nice to get a little more range out of a tank of gas.

     2. Two strokes are known for having seizing after chopping the throttle following extended WOT runs. I have heard stories that back when 500 two strokes were popular in desert racing people would setup a thumb lever for the choke so they could turn it on once in a while on high speed sections to keep from seizing their engines. Could the EFI system be modified to either richen the mixture after a short period of time to give us the full power “leaner is meaner” effect we want for short bursts of accelleration and then richen up a bit to keep from building up too much heat in the engine during long pulls (hill climbing, sand, desert, etc.) or could the system be setup that if it was at WOT for a long time to keep pumping fuel after the throttle is chopped to cool the engine? I know that goes directly against my previous issue of improving fuel economy but if burning a little extra fuel protects our engines I think most of us would be all for it. Additionally these are two things that cannot be accomplished by jetting which might give you a couple more items to add to your “Why EFI is better than carbs” list for those who just don’t get it.

133. Hello Shane

     When I build high trigger wheel count PFI engines like the Aprilia that has a 24-1 tooth count, I inject at a time that allows only the fuel charge to enter the cylinder so it is about as close to DI as possible. DI doesn’t actually wait for the exhaust port to close as there would not be enough time to inject the fuel at high RPM’s but it is injected after the scavenging has met a point that gasses are not leaving the pipe. Injection at 9000 RPM on the Aprilia DI is actually started while the piston is still on its downward stroke.

     The best way to accomplish what your asking in the second paragraph is to richen the fuel mixture based on EGT. It’s not an O2 A/F replacement rather an anti-seize avoidance. Your right, leaner is meaner until the exhaust side of the piston melts away, especially on split port designs. Since my PFI has so many fuel cells to trim based on Alpha-N TPS mapping, I can make it rich where-ever you want.

134. I should add, you can’t time the fuel very well with a single trigger CDI system so the best thing to do is convert the CDI engine to a high tooth count inductive coil ignition system.

135. I would imagine in that case you would be seeing reasonable gains in fuel economy, and that the gains would be higher at lower RPMs since you wouldn’t have to fire the injectors as long. Have you actually seen much in fuel economy improvements (especially when not running WOT) on any of your carb to FI conversions or is it still a bit soon for that?

136. Economy capabilities are there but I haven’t built an engine yet that was used other than to go WOT most of the time. You have to be so careful on two strokes when cutting back the fuel or your melting parts.

137. ^^An oil injector would further enhance the fuel economy (i.e. no mix injected only to lubricate), enhance the reliability (i.e. lubrication on demand), make 2 strokes more simple (i.e. no oil premix) and aid slightly with the low time to inject problem (i.e. 3% less mass to inject).
     Couple that with a lambda or egt sensor and a direct+port injection and you’ve got what seems to be a winner!

138. Been riding dirtbikes for ever & love me smokers to death. Also am a retired automotive engineer & businessman. After watching the software tuning video all I can add to this discussion is this:

     If you don’t offer model specific systems you are doomed to failure — plain & simple. Or, you better open a call center.

139. smoker-ace

     That’s exactly what we are doing. If you look at the PFI systems on our web site, http://www.highgaintuning.com/category_s/59.htm you will see only engine specific kits. Each kit is tuned on our Dyno while tuning the A/F. I have had a lot of requests for just the parts and your right… I would be doing daily tech support for weeks. Even engine specific kits have to be installed properly to perform as designed. Sensors have to be place exactly where they were for calibrating.

     There is well over 40 hours of time involved (closer to 100) to get calibrations to where I will call it my work. This also includes proper throttle body and injector flow selection.

     I have just recently moved all systems to inductive coil ignition. Injecting an OEM CDI system is a hair pulling experience. CDI has no feedback capability ran on its own and the aftermarket systems are approaching the cost of the entire HGT System. Inductive coil is 100% feedback and our ECU controls not only the curve but idle control through advance. This is very advantageous when controlling big bore engines.

     Inductive coil ignition requires a complete redesign of the ignition system from the flywheel to the ignition coil so it is taking some time but you will see some very cool stuff releasing soon.

140. So will we see a engine actualy run with this crap, or will it be another crash and burn?

141. http://youtu.be/IXzvvfQK3Xs?hd=1
     

142. What are some crash and burn examples?

143. Has anyone tried the Ecotrons kits? I’m curious as to how they work, how it differs from the HGT kit, and why it’s less than half the cost.

144. Coming from a road 2-stroke side of life, would you guys be interested in supporting both RGV250 VJ22 2-stroke engines and RZ/RD350 Banshee engines?

     There are a lot of those around on the road throughout the world especially the 350 with Yamaha producing new parts for them in India. It would be the bees knees to be able to have your system on an RGV250 solving a few of the issues with the carb system and keeping many road smokers happy. There is also the Two Stroke Shop in Australia which is working on a RS500 2-stroke based on a modified 350 Banshee engine and they would well be interested in your system as well for their bike.

     Not just about the dirt although – I love that as well, but also taking it to the street where we can put the thumpers to shame there as well.
     Call it payback Honda.

145. We have a 350 Banshee in the shop now for a conversion. I have 3 projects in front of it but will be getting back to it soon.

     TSS is no longer doing the RS500. That fell apart with a lot of investors out their parts and money.

146. That sucks to hear about the TSS RS500 and subsequent fallout for investors.
     Haw about the VJ22 RGV250 which would also fit the Aprilia RS250? Adding some grunt down through the revs as well as more throughout the rev range would make these bikes great especially for track fun.
     Hell just going from stock to Tyga Pipes on a VJ22 RGV250 opens up a lot of fun but there is a throttling issue around the 8k rev mark where you end up with a flat spot and an electronic system would eliminate that. I always feel like I’m getting on a bus when I go from the RGV to my CBR1KRR. yeah the thumper is silly fast but just not fun and throw-able like the RGV.

     I hear there is a mob in the states doing injection for the banshee in 4-wheeler guise which transforms it into a hell of a lot of fun. They can run it on E85 and pump out 90hp I believe from the 350 engine and that is with straight pipes (no YPVS or expansion chamber), imagine doing it on a YPVS based banshee engine with decent aftermarket pipes….

147. I have sent Charles 144 engine back as it is now needed for events etc. Being a “get to it when you can” project with all the other high priority engine builds we do daily and changes we have made to ignition control it will be best to schedule a specific time when we can do the work from start to finish.

     Most every PFI system now built (with the exception of drag racing) is using a high tooth count reluctor for Inductive Coil Ignition. CDI is not the way to go for anything fuel injected that you want to idle. Not only that, it’s just a bit dated. For dirt bike use, it is a much better system and current with technology.

     I am Dyno testing a 500cc 2T this weekend (if all goes well with the weather) that we have just finished. It has been completely switched over to PFI with Inductive coil ignition using a custom 12-1 reluctor and nice charging coil for future accessories. Start-up, Fast idle and warm-up are using today’s technology. Initial testing has been awesome so I am looking forward to some nice results.

148. Hope you got a before modification dyno run for comparison.

149. HGT how and where can we see the 500cc results or even a video?

150. HGT, I have found this thread very interesting, and am going to make some time to go back and watch all of the youtube videos as soon as I get some spare time. What I find most interesting is the new ignition systems that you are working with. I love the thought of converting to EFI, but I run 100 mile desert races and battery changes are out of the question. I ride a ’06 KX 250 and the CDI doesn’t put out enough for any kind of charging, much less a lighting circuit output which would come in handy for the many night races during the hot summer months. I am not an engineer, so you lost me with the “high tooth count reluctor for Inductive Coil Ignition”. Can you explain in laymans terms or direct me to a link for this type of ignition?

151. I would really want to see that 500 dyno or video!

     2 Strokes are slowly coming back, even in competition classes. So A good and easy tunable after market PFI system should sell very well in the future!
     The only thing that’s holding me back for a while (and I assume a lot of other people) is the price vs limited real world feedback. If you could knock of some $$ it would boom a lot more. Throttle body’s need to work, not look like there from a NASA space shuttle engine.

     Nevertheless A big thumbs up for your work and progress, your really a blessing for the 2 stroke community!

152. I will release the results when I have permission from the Owner.

     Stay tuned.

153. Does your ECU also control the power valves?

     I would be keen on a RGV kit too!

154. I don’t think the HGT ECU can control the power valves, for the RGV you could also use the programmable ignition from Zeeltronic. That’s with power valve control. http://www.zeeltronic.com/

155. is the reluctor, charging coil, and ignition something that HGT will produce or will this all be 3rd party parts that will have to be bought if the customers application requires it? if so, can you please post info on those needed parts so i can research and budget for the project.
     patiently waiting on 500cc 2T results!!

156. Hmmm the fi section on the hgt website has completely disappeared,well atleast i cant find it anymore,not sure if this is a good or bad sign???
     also waiting on the 500 results, tic toc

157. It’s been an extremely busy winter and spring with an all new PFI offering for 2 cylinder and 4 cylinder 2 strokes. The 500cc is getting transitioned to our new OBDII PFI ECU.

158. just a quick thought,mainly on the off road side of things,some technologys great,but do we risk sending 2 strokes the same way as 4s,making them expensive,heavier and harder to work on with fuel injection etc? at least if i have problem with the carb i can easily strip it out and find the problem.

159. I Want a fuel injection kit for my snowmobile. It is a classic Rotax powered triple 700 two stroke, nothing has such a satisfying cadence as you cruise through the Norther Minnesota Forest along the edge of Lake Superior. They don’t make em like this any more. My Wife Survived cancer and I came back from paralysis so we are going on a memory ride next February 2013 and I am starting this project now. My wife’s breast cancer Survivor Group is putting the ride together as we speak. The hood our our sled is having the Pink Ribbons painted on it now and she has been on the phone for a week now calling our riding friends and spreading the word.

     I am so happy I came across the HGT Blog and site that I found through Google.

     My goals are to combine the EFI and CDI into an integrated unit with three individual crank triggers to eliminate wasted spark and get the highest possible arc voltage, make a slight improvement in reducing fuel consumption, have a cleaner foot print and enjoy the lack of hassle the EFI sleds have with E-10 gasoline and the phase separation that plagues carburated snowmobiles.

     In addressing the market potential, Ski-Doo, Polaris, Arctic Cat and Yamaha all were very proud of their triple cylinder powered sleds. The natural balance of a triple cylinder equates into a smooth ride, a natural cadence in the exhaust note that is pleasing to the ear and in addition the noise canceling effect that three cylinders have.

     The technical revolution in touring and trail performance suspension and variable torque drives peaked in 1995-1998 for all the manufacturers. Add to this that we were in good economic conditions at that time and a boat load of these $10,000 to $15,000 luxury touring class snowmobiles were sold. Polaris was the first to the market in 1991 with their Indy 650 RXL EFI sled in 1991, it was not very successful and many were converted back to carbs. By 1993 all manufacturers were working hard on EFI variations to meet emission standards. Every good After-Market EFI Conversion that is going down the trail will get the attention of some one who lacks it and they will ask. My hood will be painted with “Powered by EFI Rotax Triple, you know you love the sound and the power, ask me how” Call me on helmet Chatter Box Channel 2.

     As a touring rider I ride conservatively and my wife is always with me and we take great care of our snowmobile. We love to ride and the weeks where the snow is good are precious. EFI Sleds always run good. I want EFI. I am typical. Like every one I ride with, we have been looking for a good after-market EFI System. Here is the picture: A new 4 stroke EFI touring sled is $12,000 to $15,000 now. I paid $11,025 for my 98 GT SE. The 700 and 800cc 2-Stroke triples are very powerful and fast, you need to be thinking in the 750cc to 1200cc 4-stroke turbo to get back to that level of arm straightening when you pull the trigger. I have talked to numerous riders whom do not think $2000 to $3000 maybe $3500 is too much to pay for a modern no wasted spark EFI/CDI system that is designed to deal with the ethanol laden E-10 fuel.

     I read the well thought comments from the MX and Enduro style riders whom just reach under the tank on an engine that is mostly hanging out in the open to change their needles in their single carb dirt bike. On most touring snowmobiles with detailed insturment clusters, live compressed air suspension, liquid cooled engines, large still air boxes the carbs are plumbed into, plus three carbs in tight quarters and in my case with the Mikuni pressurized float bowl system that have a pressure and vacuum electronically modulated solenoids, air and engine sensors, 50 miles of wire and tubing, a crankcase pulsed pressure/vacuum pump system for the fuel ratio mixture system, it’s an all day job to change the needles and main jets. Ok even though it’s not EFI there as still electronic throttle position sensors times 3. I will gladly pay $1000 a burner for a clean fuel rail and return line system and no less then half of the spaghetti under my hood. Ok did I mention every couple hundred miles pulling every thing apart on the induction track to pull the slides out of the carbs, pull them out of their boots on the engine on and on, remove the float bowls, dump out the ethanol goo, rinse everything in SafetyKleen compressed air blow out of every thing and put it all back together because the changing of pressure in the float bowls to control mixture makes the crapy e-10 gas phase separate in cold weather. Maybe the KDX rider can’t justify EFI but I can and happily and now!!!

     Check out these videos, as 2-cycle HGT EFI Geniuses these brief video clips of Ski-Doo Grand Touring 700s and 800 triples, especially the 3rd clip here where you can clearly see the tach and speedo and hear the shift out will probably tell you what fuel map and ignition curve needs to be programmed into your unit.
     the only thing that would make this any more fun would be a little more fuel mileage and the always smooth performance of an HGT EFI System: GT SE High speed pass: http://youtu.be/jQdG_v0qDoE 100+
     Typical ride taking it smooth and easy and this is the way we ride: http://youtu.be/1OQv4joi3eo Smokin high speed Grand touring SE, you can see the tach and speedo and hear the shift out at about 135 then a sustained high speed cruise mode at about 80-90, we come across many frozen lakes 2-5 miles long or more where on a good marked trail we know is clear I will hold it at 80: http://youtu.be/rsSBEPi-TO0

     One of my goals in upgrading my Ski-Doo to a fully pressurized circulating fuel loop EFI is to eliminate the problems of E-10 gasoline in cold weather. EFI and direct injection snowmobiles do not fight the phase separation that occurs in ethanol blended gasoline. There is a big market for a KIT EFI system that is pretty well thought out. Especially for the triple cylinder engine riders, all of the factories eliminated the 3 cylinder engines by 2002 in favor of 2 cylinder SDI (semi-direct injection where the injector nozzles are in the transfer passages between the crankcase and cylinder) throttle body injectors or voice coil direct injection through the cylinder heads directly into the cylinder.

     My application is a 1998 Ski-Doo Grand touring SE 700 snowmobile. Corollary: Honda Goldwing of Snowmobiles. Rotax BRP 699 3-cylinder, RAVE cylinder exhaust pressure driven exhaust port height valves, factory triple heat and acoustic insulated expansion chambers and an exhaust tubing system from the center pulse chamber to the humongous resonator that would make a Ferrari owner proud, case reed induction, Gear pump and line routed oil injection system in the crank case, this system is really effective engine lubrication system. Presently it has three 38mm Mikuni round slide with the electro pneumatic DPM system that pressurizes the float chambers on the carbs to control the mixture. A micro controller, 50 miles of wire, a pressure and vacuum pump, diaphragm type that is run by the crank case pressure pulse. This snowmobile is powerful smooth and fast. It is a gas guzzler we start looking for a fuel stop at 100 miles. The snowmobile always runs rich. The main tank is 10.5 gallons and the auxiliary tank is 3.5 gallons. At 100 mile fuel stops we will take on 9-11 gallons depending upon trail conditions how much we are carrying.

     The torque converter engages at 3500 rpm and shifts out to hold the engine at 8500 rpm under full throttle. Typical trail rpm is 4500 to 5500. See the video above here to see how fast you can cruise if you like. I am told this particular Rotax 700 triple is a 135+ hp engine, what I do know is that if you have a mile of frozen smooth lake in front of you with good packed snow, this snowmobile pushes the speedometer easily into the the triple digit zone and pulls hard to 8900 rpm and then starts to finish shift out. I have never had the guts to take it past 115. And then it loafs along happy at 15- 30 mph all day long and because is was carbed and now EFIed it will not e-10 goo-up and it will be better mileage

     While this Ski-Doo is mechanically strong and well built, it’s electrical system in 1998 was a nightmare so I built a wiring harness system for it. I want to take this all the way this summer and hope to find an integrated CDI/EFI System. I am very happy to have found your site and blog here.

     Very sentimentally attached to this particular snowmobile my . Why? My wife survived breast cancer and I came back from a form of paralysis, we have not ridden in a while so for the winter of 2012-2013 we have retired and are planning a memory ride, that will depart Hugo, MN the 1st week in February 2013 going north on the Hwy 61 rail line trail to Duluth, then on to the MN Corridor trail system to Blufin Bay Lodge on Lake Superior in Tofte. Then back down to Two Harbors and turn away from Lake Superior heading mostly North West on the big corridor trail to Side Lake, Minnesota and a long rest. Then heading south again back to Hugo wich is on the NE corner of the Minneapolis/St.Paul area. We have no minimum schedule but can do a minimum of 100 miles a day. In our younger days we have had more then 300 mile days gliding through the Northern Minnesota forest and bog land trails.

     Thanks for reading my story and I am looking forward to being your customer. I am an electro-mechanical (retired) engineer and have a CAtia solid modeling system, I can send you IGES, STEP, STL, Native Catia model of the still sir box, 38mm Mikunis, cage reed boots and engine bay if it will help. Check out my web site, if you like machinery you will not be disappointed Also a detailed electrical schematic of the current system. What I am seeing is a whole sale replacement of the stator, magnet wheel, trigger coil etc, or saying here is the hot from the voltage regulator, AC ground buss and the DC ground buss, pulling out the Ski-Doo DPM, DESS and replacing it all with a nice aluminimum extruded box with a couple high density WeatherGuard connectors and a serial cap plug, building or may bey fitting a nice tefzel harness and having the throttle bodies red anodized.

     Ok, thanks again so much. Gold stars to you for your work on a 2-Stroke EFI System. Long live the Rotax Triples and even longer now with a great HGT EFI System, I hope.

     Sincerely,
     Lyle

160. Other than seeing it on video here does anyone actually know of some one other than the seller that has one running on there two stroke
     I did a google search but all I can find is disapointment and arguments from the company
     http://twostrokemotocross.com/forum/index.php/topic,3265.105.html
     http://www.ninjette.org/forums/showthread.php?t=74579&page=7
     http://www.rzrd500.com/phpBB2/viewtopic.php?t=7530&postdays=0&postorder=asc&start=135

161. Nice one Jared (AKA WaxHead from Australia.)
     Are you still mad our Engine smoked you in the 24 Hour LeMinz?

     You know, there are better ways of doing this than dissing myself, the owner and his 3 riders on open forums… Build a new engine for endurance, not drag racing around the track. 24 hours is a long time to run WOT.

     You have been thrown off of 2 forums this week for posting the very same trash… 3rd time for the Aprilia forum where you can find dozens of videos from owners.

162. Has there been any progress on the Banshee conversion? Please update with some photos and tech information when possible.

163. Quote: “The 500cc is getting transitioned to our new OBDII PFI ECU.”

     What is the OBDII system? I am not sure if I have seen that mentioned anywhere else. Also, how is the 500cc coming along