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Perhaps you should first explain to some members like Larry what a snowmobile is and why indeed they are relevant. I have been promoting this tech for some time now (well over two years) on this sight only to be discounted by wackos like Larry and his downunder sidekick Aushole. BTW, that engine puts out 163 hp, not 155..... Having test-ridden a few sleds powered by this engine (with considerably more saddle time on the smaller 600 cc version), I can attest that it runs spot-on and pulls like a freight train. F**k V4s, bring on the DI two-strokes I say ! The touring guys can keep the V4s, they are smooth after all.......

BTW, the outer crank bearings are sealed (and run in special IsoFlex grease). Everthing else (including the guillotine in the 3-stage power valve) gets oil fed by an electronic oil pump (for ultra-precise calibration and dramatically reduced consumption). NO smoke, no smell, and better fuel consumption than a four-stroke. Two-smokes no more!
 

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Discussion Starter #3
Well some people cant see past thier own ignorance. I for one enjoy differnt engine architectures and can appreciate them for the advantages and disadvantages each one brings.

back on topic though, Mikstr you have ridden this motor? what kind of RPM's did it turn? was there a noticable hit in the powerband? how was it off idle?

I will always have a soft spot for 2 strokes..
 

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I'm convinced that a DI 2-stroke sbk would smoke the competition , but (except for a few knowledgeable enthusiasts) would there be a market for such a beast considering the hegemony of 4-stroke orthodoxy on the sales floor and racetrack ?
 

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engine peak rpm is 8150 and the powerband is very smooth thanks to the DI and three-stage power valve. The engine operates in stratified mode (resulting in an air/fuel ratio of 60:1, MUCH leaner than stoichometric ratio in homogeneous mode) up to about 2500 rpm then switches over to homogeneous mode. The idle is low (just a tad over 1000 rpm) and VERY regular (more so even than on a four-stroke in fact). It is only slightly heavier than a conventional two-stroke (meaning it is a hell of a lot lighter than a four-stroke) while running clean as a whistle (at low rpm, it emits significantly less CO than a comparable four-stroke, for example). This particular engine is based on the technology that won Evinrude/BRP the EPA's Clean Air EXcellence Award (something no four-stroke marine engine has ever achieved). I spent a great deal of time talking to the head engineer for Evinrude about this technology for an article I wrote and have since spoken to some of the engine guys who adapted it to snowmobiles. A fascinating technology. The best part is, it works.
 

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It's great to see Bombardier leading the way with this. Maybe we can finally start seeing some proper Canadian motorcycles.
 

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They have a patent on the injector technology, the key to the whole thing. UNlike the Orbital system, the E-TEC doesn't require an air pump. Based on the voice-coil used in a speaker, it's a clever and effective design. Quick too as they have tested some in over running over 10,000 rpm. Rev an 800 two-stroke that high and 200 hp is easily within reach, all with less weight (and weigh less complexity and fewer moving parts) than a 600 four-stroke. Anyone whose brain is not infected with the V4 virus can appreciate this.....
 

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I think the next biggest problem for 2 strokes is the lack of torque and thus having to rev so high. The average driver already drives around with their poor 4 stroke engine pinking like mad, how would they ever get a 2 stroke to move?

Pete
 

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I think the next biggest problem for 2 strokes is the lack of torque and thus having to rev so high. The average driver already drives around with their poor 4 stroke engine pinking like mad, how would they ever get a 2 stroke to move?

Pete
lack of torque? Two-strokes produce over 50% more torque for equal displacement than four-strokes. The issue is most commonly that two-strokes are asked to compete with a serious displacement disadvantage, forcing tuners to go with more radical tuning (and hence peakier powerbands). Electronic controls and such features as the three-stage power valve have gone a long way to closing the gap. In my discussions with the project leader for the E-TEC, we touched on this topic and he noted that if the engines are given equal displacement (for equal output), the E-TEC smokes the cammers across the rpm range (out of the hole torque being critical for a boat motor, they obviously researched this question with particular interest).
 

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Bombardier is already half way there with Can Am



You think they're planning to eventually get their two stroke into something not too different from the roadsters they make? Maybe take it to two wheels in the nearish future?
 

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If anyone is gonna make it happen it's gonna be Bombardier. They have established their dealer network and reputation, so they can get away with this sort of new market :)
 

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DI two strokes are an excellent technology. I personally would buy a lightweight sportsbike fitted with such an engine as soon as teething bugs have been ironed out. :rockon

But there's a catch: legislation. DI 2 strokes can satisfy present emission regulation no problem. But how will future legislation be? While the general technical consensus in Europe is that emission legislation for motorcycles should be left as is (coming up with new legislation is expensive and returns are negligible), Honda has been lobbying at Brussels for new legislation to effectively ban two strokes and it looks like they may succeed. While Honda's visceral hatred of two strokes may seem like the natural cause but there are much more mundane causes. The bulk of their sales in Europe is made up of 125-250cc scooters in countries like Italy, Spain and France. This domination has been chipped in recent years by Asian scooters. If a large manufacturer with a good sales network like KYMCO (Taiwan) were to struck a deal with Bombardier to build DI two stroke engines in China Honda would surely lose more of this lucrative market. This is exactly the same tactics European car makers are using to keep their Chinese rivals out of the door: it has nothing to do with saving the Papua fruit bat from extinction. And it isn't working, at least judging by sales figures of Great Wall and DR (Chery) vehicles.
In such a climate it's obvious that Bombardier doesn't want to throw away money investing in a powerplant that may soon be banned.

PS: Aprilia, which has long been using Rotax engines, actually built a number of DI two strokes prototypes using RS250 frames, suspensions, fairings etc. So you may get your wish one day... ;)
 

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If it don't go rinnnnnnnnnnnnnng a ding ding and smoke I ain't interested...
 

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Not sure what Larry had to add there but it is surely insightful and productive, especially given his intimate knowledge of the E-TEC technology..... Oh wait, the dude doesn`t even know what a snowmobile is..... More V4 coke delusion...:p
 

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DI = I'll miss the smoke of a politically correct two stroke...

 

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Speaking of already happening...

The Two-Stroke Shop 2-Stroke Shop

Take your chassis and add the motor already built. Yummy. I am thinking my little SVS would be great with a solid 400-500 2-stroke in it. Then you don't need the gov telling you it won't pass inspection. A cop would most likely not know the difference. :)
 
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