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I think the recent advancements in 2 stroke outboard motor technology include switching to 4 stroke.

Needless to say, I'd buy one of these in a heartbeat. My guess is that it will never see the light of day.

2009 Yamaha RD350 Concept
 

Original Article:
2009 Yamaha RD350 Concept

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RZ350 motors were 64mm x 54mm, the cylinders in the illustration seem to have a shorter stroke, any guesses about intake reeds/rotary valves?

Man, that looks like it would be a whole lot of fun. I agree with Buz; we'll never see it produced, though.

I think the coolest sound in the world is a 501 Maico. Hearing one winding out, with the lingering smells of Blendzall, cut grass and cow poop in the air on a chilly wet morning....what a lucky time to be a kid. I think the only thing better would be to watch and hear a squadron of Spitfires take off from a grass field.

Oh fer chissakes...
 

If it burns oil, it'll never fly. Snowmobile or no snowmobile tech.

...how many times MUST I remind everybody that the two stroke will never be "emission legal" until they resurrect the "Orbital" two stroke design that Ford killed off in the mid 80's (that they put in Escort rally cars).

Two stroke top end, pressurized intake injector, exhaust port with a dry-sump 4 cycle type lower end. Doesn't burn any oil in the combustion process.

The Ford Escort put out over 200 HP, and the entire motor assembly weighed about 120 lbs.

I could go on about the Detroit 2 stroke V8 diesel, but no one would listen...

I remember the Orbital. It was made by an Aussie company I believe.

Yeah, think it was an Aussie division of Ford that perfected it. Used a roots-type supercharger to pressurize a bottle that was hooked up to the intake injector. You had to spin the motor for a few seconds to get the psi up, then the motor could start. In some twist of fate, GM bought the patent from Ford, and killed it off. Guess having a motor last for 20 or so years with no major repairs in a no-no in the eyes of car manufacturers. Like the saga of the slant-six, there's little recovery in manufacturing costs or spare parts and repair $$$$...if it don't break down.

Bring em' back I say. I bought a Mach IV complete with expansion chambers just to piss off the next door Harley guys. Hey, if they can drop the clutch at 2am when the bars close, I guess its ok for me to wheelie down the street at 5am going to work.

Love it, looks beautiful and would be wonderful if it got here... To be honest i'd welcome ANY sports bikes/naked bikes between 250 and 600(Two or four stroke) there really isn't much choice in that area, Personally i'd love to have an Aprilla RS500.