Direct injection keeps two-stroke alive for Bombardier in 2012
The last major bastion of the two-stroke engine appears to be in snowmobiles. Thanks to liquid cooling, electronic controls, fuel injection, sophisticated combustion techniques, and variable-exhaust-port technology, the latest avalanche of two-stroke “sled” powerplants aims to comply with the new U.S. EPA Phase 3 emissions regulations slated for the 2012 model year.
Can the two-strokes, with their impressive specific output, high power-to-mass ratio, and package benefits, hold their own against the four-stroke assault?

Electromagnetic injectors mount vertically on the liquid-cooled 800R twin's cylinder head. In this cutaway view, note the internal coolant passages; the engine circulates fuel to help cool the injector.
Bombardier Recreational Products (BRP) engineers believe they can. BRP’s evidence is the recently unveiled Rotax E-TEC 800R, newly equipped with direct fuel injection (DI) and slated for 2011 Ski-Doo sleds. (BRP owns Rotax, Ski-Doo, as well as Evinrude marine engines and Sea-Doo watercraft.)
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Comments
By Sachsgs250 on April 28th, 2010 at 11:06 pm
This motor is rated at 155 hp! Can you imagine a 400cc dirt bike based on half this powerplant? I’m thinking some kind of “traction control” would be needed.
By 2STROKEREVOLUTION on April 29th, 2010 at 4:06 pm
This is a big improvement. I have been following the E-Tec sleds since the 600 came out over a year ago.
The 600 E-Tec with 130hp gets 21mpg. The 1050cc Yamaha 4-stroke with 130hp gets only 19mpg and weighs 100lbs more. This new 800 E-Tec makes 155hp and gets 18mpg. That is only 1mpg less than the Yamaha while making 25hp more! It also weighs about 80lbs less. Same MPG, less weight, more power, wider powerband, cheaper, and less maintenance. What does a 4-stroke do better anymore? Nothing.
By RM500 on April 30th, 2010 at 5:29 pm
So tell me. WHY havent any bike company built a DI twostroke dirtbike yet?? (or streetbike)
The technology and knowledge is far from new. Is it just business politics?
Its something fishy about it… is the pro 4stroke companys buying out this “THREAT” ??
By motoman465 on May 2nd, 2010 at 10:47 pm
I am sure most of the manufacturers have direct-injected two strokes, but they make more money from the four jokes! If you look at it from a business stand-point, it makes sense to keep those DI two-strokes off the market until someone else releases one, then the others will release theirs in order to keep up and not lose any market share. The big 4 did the smart thing to increase their bottom lines with the four strokes and all the marketing hype. They just didn’t count on the public starting to wise up to the negative aspects of the four strokes. I still firmly believe that the two strokes should live right next to the four strokes. What is good for one rider may not be good for another. We want the ability to be able to choose what we want to ride/race!!!
By 2STROKEREVOLUTION on May 3rd, 2010 at 2:01 pm
@RM500
At the time of the switch to 450Fs & 250Fs the manufacturers realized they could profit more from a change to 4-strokes. If they advertise them as much better people will be willing to pay a premium charge. With the go ahead they put in a lot of development and advertising money. Why would they want to switch back with all that invested money?
By 2STROKEREVOLUTION on May 3rd, 2010 at 2:03 pm
@motoman465
I am a believer in choice for dirt bikes too. I own a KTM 380SX (2-stroke) and a Honda XR250 (4-stroke). But when DI comes to 2-strokes there is not a single benefit of 4-strokes so might as well rid the world of those expensive, overweight engines.
By VintageBlueSmoke on May 11th, 2010 at 11:18 am
Bring back the 2-stroke Can-Am Motocross bikes! I still race my 1980 QIII 250 in local Enduro and motocross against modern bikes. I’d buy a new DI Can-Am MX’er. MX7 anyone?