Two Stroke vs. Four Stroke – Let the debate begin
Whenever the debate between two strokes and four strokes begins, proponents on both sides bring up various reasons to defend their position.
In many cases, real facts with proof are ignored, misused or misunderstood. At times, the arguments boil down to hearsay. Some of it blatant lies.
This is has created a divide between the 2T’s, the 4T’s and their supporters. Each side becomes defensive and many times useful discussions turn bad quickly.
This is bad for our beloved sport of motocross.
Every one has an opinion and they are entitled to their opinion. But at times that opinion may not be based on facts.
Let’s look at some of the most commonly stated reasons four stroke racers and two stroke racers debate. I will not go into detail on any of them right now, but just get them out on the table. We will examine each in depth over the following weeks and months.
Yamaha YZF engine cutaway.
• Four Stroke technology has surpassed Two Stroke technology. Many four stroke supporters say that the two stroke has had it’s day and it’s now the four stroke generation.
• The EPA (Environmental Protection Agency, USA) has a ban planned for all Two Strokes, so the manufacturers had to switch to four strokes, beginning in 2010. Since California has the strictest environmental laws and all four manufacturers have their US headquarters located there, this ruling would have a huge impact.
• The four stroke revolution has brought about higher sound levels that threaten to destroy motocross. While the sound of a two stroke may be louder when you are right next to it, as compared to a four stroke, that sound does not carry near as far. The booming four strokes can be heard for literally miles away. This has lead to riding areas being shut down and anger among neighbors of riding areas.
• The FIM / AMA rule change allowing a displacement disparity between 2T and 4T race machines. This was unprecedented in all of racing. It was not just that they allowed an advantage, they allowed the four stroke to be double the displacement of a two stroke.
TM Racing 125cc engine.
• The four stroke bike is easier to ride fast and they inspire confidence. Jumps that would have been impossible to perform on a two stroke are easy on a four stroke. But is this a mixed blessing? Could this be the catalyst that has lead to racers getting injured, because they had taken a shortcut in their racing education?
• The cost of racing has increased dramatically. Just the exhaust system for a 4T costs at least double if not triple the cost of a 2T system.
• The upkeep, rebuilding and maintenance costs are much higher for the 4T than the 2T.
• When is a DNF not really a DNF? In professional racing, there is now a phenomenon when racers fall or stall and they are unable to restart their four strokes. The result – lost races and National Championships because a highly paid professional racer can not restart his race machine.
These issues are just some of the challenges that our sport is facing. We are not only in danger of losing the two stroke, but the future of motocross could be in jeopardy.
Over the next few weeks/months I will explore each of these issues in depth, supported by facts from relevant sources. It is time to leave the emotion-based opinions behind and work together to build our sport up to new heights.
As always, I am interested to hear what you have to say on this subject. Please feel free to leave a comment below.
Boxing photograph entitled “One on One” by ElMarto – Flickr
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Comments
By 2smoker on January 16th, 2009 at 11:40 pm
Ok, Where should I start?
By 2smoker on January 17th, 2009 at 1:42 am
Since the introduction of modern Four stroke, the sport lost his “sex appeal” . There is no substance. I wish to see a modern 2 stroke hit the market with EFI and updated frame, look and same displacement as the four joke.I’ll be buying 2 of these! I’ll be more happy than Obama when he got elected!I love my sport to death, just sad to see it manipulated by racing organizations,manufacturers and the medias because WE riders should have the last word on any changes concerning it.
By yaman on January 17th, 2009 at 8:32 pm
SIMPLE! 2 strokes rock!, 4 strokes suck!, end of!.
By warburtonm on January 18th, 2009 at 3:35 am
I’ll start with your first point, that 4T technology has surpassed 2T technology: even if true, so what? That’s like saying that the violin has seen its day and it’s time to replace it with the electric guitar. All that matters is getting across the finishing line first, or having a good time riding the bike. Who cares what the relative level of technology is? Truly a specious argument.
By The General on January 18th, 2009 at 2:59 pm
Thanks for the comments!!
Hey warburtonm, I agree with you 100%!
To clarify, the list I made was collected from my experience of reading message board arguments between 2T and 4T’s.
To me the non-nonsensical part of this is the people that say that 4T technology has surpassed the two stroke, why do they leave out the displacement disparity? How can a technology be better when it has to be twice as big?
It does not compute!!
Stay tuned for further articles that will address each of these “conversation” starters in greater detail.
By Honda2strokes on January 19th, 2009 at 2:42 am
2 strokes rock.period. 4 joke technology might be advancing, but it doesn’t make them any better or more reliable(actualy less). I would like to see bubba hop on a yz250 and kill the 450’s
By VintageBlueSmoke on January 20th, 2009 at 11:26 am
What I would like to see is a less emotional response to the 2 stroke (2T)/4 stroke (4T) debate and more substance. For instance, technology wise, the 4T has developed extensibly since the FIM/AMA established the double displacement rule, while the 2T has had very little changes. If you were to compare an EPA legal 2T to an equal displacement EPA legal 4T, how would they match up?
In the 1970’s, when all cars had to adopt strick EPA codes, we pulled the smog devices off the cars to make more power. However, today we can make more HP from smaller engines and still be environmentally legal. I foresee the same with motorcycles. If the FIM/AMA were to change the rules and make all racing machines meet a strict standard for emmissions and noise – and enforce that standard at the events, it would be the same for everyone and the aftermarket would eventually find the lost HP.
Of course, we would all “strip that junk off” our non-race bikes for awhile, but then we wouldn’t be able to race our stripped bikes at FIM/AMA events and eventually we, the masses, would adopt the cleaner motorcycles.
Make no mistake, the manufacturers jumped on the 4T bandwagon because governments and the FIM/AMA put pressure on them to do so. Those organizations are the only ones who can save the 2T.
By 87cr500rider on January 20th, 2009 at 8:31 pm
My big problem with 4 strokes is the displacement advantage. Noone would ride a 4 stroke if they had to race against 2 strokes of equal displacement. I don’t find it easier to go as fast on a new CRF450 as I do on my 87′ CR500. Sure the suspension is better on the 450, but it’s also slower and doesn’t turn much better and the lap times don’t lie. Throw that engine in a modern frame and it’s no contest. Case in point a buddy just finished his aluminum framed 500. It’s an 04 chassis. He took it to the track and let everyone ride it, including a local pro. The kid had never been on a 500. He came back in and said his 450 didn’t have anything for it. That kid is a 4 stroke fanatic but got a dose of reality that day. That’s all with a stock carburated dinosaur engine and an out of date chassis with stock suspension. We don’t even have to get into engine rebuilding costs.
By eprovenzano on January 27th, 2009 at 10:21 pm
2 Stroke technology has been at a stand still for many years. KTM, GasGas, TM, Husky and a few others are trying to improve the technology. Yamaha still mfg smokers, but pushes the 4 stroke. Suzuki is getting back into the 2 stroke, but not in the US. The problem is the all R&D had been put into the thumpers. The real question is, What are the Japanese MFG’s afraid of?… They are afraid that since they’ve dumped so much into the R&D of thumpers, that a smoker with yesterday’s technology will….. “smoke” their thumpers. (Pun intended).
Please do away with the class limits, let the classes be based on CC’s. Thumpers have evolved to where they do not need the protection of double the displacement, Since Honda and Kawi have both dumped development of the smokers, only Yamaha, and Suzuki (outside of the US), still mfg smokers. KTM, GASGAS and a few others are still improving on the smoker.
In today’s jump fest SX tracks let the rider choose what he wants to
ride. I can see in SX that depending on the track, a “professional”
racer switching between a 2 and a 4 stroke. Example Anaheim… Pretty open track, a smoker would have done well. Houston, really tight, a thumper may have been the stead of choice. Now in MX, that’s a different animal. I see more smokers than thumpers at the starting line. Off road racing, 2 strokes are still the bike of choice for many a rider, but that choice is being taken away as we are stuck with less and less choices. Plus an amateur cannot afford to competitively race a thumper. It just too expensive to rebuild, or repair after a weekend race.
Its just a sad state of affairs that the MFG’s are the one who decide the fate of the 2 stroke machines, especially since they know an out dated 2 stroke 250 will thump a modern thumper.
By VintageBlueSmoke on January 30th, 2009 at 6:21 pm
I can tell you what the manufacturers are afraid of. They are afraid they will have their market closed because of emmisions. As stated elsewhere, a modern 2 stroke motorcycle is the particle emission equivellent of 10 cars. Thumpers are cleaner (still not clean as a car) so to prevent government regulation, they have gone to the dark side.
I would be very interested in comparing like machines. Same cc cylinders, same particle emmisions, same noise level. I believe the thumper would win (that is until R&D was put into the 2 stroke).
By shidler669 on February 16th, 2009 at 2:18 am
There is a reason why the best riders of the time (carmichael, stewart, and reed) were the last ones to switch to four strokes.
By westyz on March 12th, 2009 at 2:38 pm
Thought this might make an interesting post –
I live in England and I’ve always loved 2 stroke motocross bikes. I went out to Thailand a few years ago and had a blast with a mate hiring some 2 stroke 250cc Honda and Kawasaki KDX’s, we were in paradise in the middle of a tropical island in the summer racing around together on these bikes with huge powerbands – it was amazing.
When I got back to England I thought it was all over when I found out about a law that means we can register any off road motorbike for on road use, fully road legal – it’s called ‘Enduro Exemption’ and means so long as it’s an off road machine we can by-pass the usual controls associated with registering normal motorbikes and cars.
I found out about it by chance after I saw a KX250 2 stroke for sale fully road registered on ebay, I looked into it and found it was legit so I bought the bike and then since that time I’ve bought my brother a YZ 250 and we registered it ourselves, it only costs £50 and a few forms! Insurance is about £125 a year and road tax £35 a year thats all it takes.
The best thing about it is we don’t have to modify the bikes to get them road legal – all we had to do was put a mini license plate on the rear mudguard and a battery powered horn. Both our bikes are straight off the race-track, propper motocross spec, no lights or anything (we have to stick out arms out to ‘indicate’ lol..) I added a speedo so I know who fast I’m going in case we go past a speed camera but thats pretty much it! I still have my knobblys on!!
I know some people say ‘why put an off road bike on the road its stupid’ but I love the 2 stroke 250’s. I know dirt tracks are fun but personally I dont want to have to only be able ro ride at dirt tracks, apart from the fact there are not many around here and its quite restrictve in terms of having to go round the same piece of land over and over and I want to keep my bike in perfect condition..
So now me and my bro can get on our bikes whenever we want and ride where ever we want, no limits at all. It’s absolutely amazing – everywhere we ride we turn heads, people just don’t expect to see 2 guys on pure MX 2-stroke 250cc machines howling past them on the road.
At the weekends we can travel all over the place on our bikes – we even have to mix our gas at the the petrol stations while we fill up – hitting the power band at full pelt on the high street always gets people whoooping at us as we go past!!
I think England may well be one of the only countrys in the world where you can do this & it’s the most amazing thing – I love my bikes!!!
It’s such a shame and unfair that 2 strokes are dissapearing from the tracks and the showrooms, they are the ultimate machine, after finding this site I’d like to look into getting one of the new 500cc ones you featured.
We have got to keep up the pressure to bring them back!
By Chris2T on January 6th, 2010 at 8:36 pm
if you think 4T technology has surpassed 2T technology, you might want to check out the following website:
http://www.ski-doo.com/en-US/
click on the “E-TEC and 4-TEC ENGINES” tab
click the “Find Out More>” button.
click 600 H.O. E-TEC and check out the dozen or so engine animation videos.
You may never look at a 2 stroke technology the same again
Chris
By JohnNicholas on January 7th, 2010 at 10:01 pm
Chris2T – That was awesome!! Thanks…
I’d like to see how the technology can be applied to motocross!
This link might make it easier for folks to find the info…
http://www.ski-doo.com/brphtml/skidooenginetech/en/Index.htm
By Sachsgs250 on January 8th, 2010 at 6:44 pm
The twincam four valve four stroke engine was invented in Spain in the 1920’s.Walter Kaaden invented the two stroke expansion chambered exhaust in the 1960’s.The progression of technolgy is relentless and the advancements we have seen in four stroke technology were artificially induced through enviromental legislation.I personally think that the advantages of a two cycle engine,simplicity,high power to weight ratio and ease of manufacture (costs included)will someday allow it to dominate again.The almighty dollar rules and once enviromentaly two strokes can be produced in an economical fashion – they’ll be back.