RM/CR/YZ/KX250's should be mfg'd as 350's

[jmics19067]

then the engine can make 25%-50% more horsepower!

would this increase apply to only open port exhaust say on a weed whacker engine or would this increase apply to the expansion chambered exhaust on power sport engines?

the reason I ask is that the old two stroke diesals by Detroit would have cam operated exhaust valves and direct mechanical injection. I don't believe they have done any great research on making in clean burning yet the basic design should be a fairly easy beginning for such technology.

Someof the biggest hurdles of designing a MX bike is wieght ,simplicity, and ruggedness. Two strokes as we know it fit this bill perfectly with nothing outside of basic engine principles to cause it to stop running. with the EPA demands the next easiest thing to fit this bill was lightening up a 4 stroke.Although a highly advanced state of tune the four stroke mx bike is still a simple basic engine.

I am glad that there is a few companies and some high tech tinkerers out there that are trying to get a 2 stroke to comply with future mandates. With all the sensors servos and gizmos needed you are adding wieght and complexity, then you will need an alternator to run it adding to weight ,complexity ,flywheel effect and parasitic horsepower loss. Only time will tell if a first turn pile up will render an exhaust O2 sensor useless, not letting the bike run, compared to a dented pipe where the guy could effectively run poorly the rest of the moto to gather possible season deciding points.

Unless there is some amendment to the "works bike "rule I do not see complete real world data being assembled. If they are going to make a real race bike only real racing will determine if it is decent. Besides manufactures are only going to sell what they can make a profit on,If your current 6000$ machine suddenly jumps to 10,000$ how many people will buy the new technology.

 

[BunduBasher]

The engine I saw had no additional components other than a reed valve, and a diaphragm separating the crank from the gas inlet. The crank was sealed, as the piston goes up, the diaphragm contracts, and gas is sucked in from the carb into the diaphragm chamber, as the piston fires and comes down, the diaphragm expands, and feeds the gas into the cylinder via a reed valve port. looks to be a very simple design, and uses the basic principles of the two stroke. I can't see any excessive or additional weight involved.

My only question to this design is, if the diagram fails, the oil will be sucked out of the crank, and burned out the exhaust - I guess the huge puff of blue smoke would be a telltale sign, followed by a massive seizure :eek:

 

[Wind]

Real world question here for all you people: Would flywheel weight and displacement kit for my 03 RM250 give me more useable power? The 250 is great but there are rpms that are all I can handle and rpms when I want like double the power. What to do? What to do?

 

[ericlachance]

why not bring the class weight limits down. I'm sure 250's could be made even lighter, but because of the rules, racers aren't allowed to go under this specified weight limit, so say we take 5 pounds(for example) off this limit, the 2 strokes would than gain a weight and power/weight advantage, bridging the gap between 2 and four strokes...

just a thought
Eric

 

[kdxtodd]

I think it would apply to both? don't know for sure. I think The weight issue is the only thing that boyesen is having trouble with right now. There isn't a lot of info on their experimentation, but there was an article in racer x about it, october issue i think.