RM250 popping under acceleration, power delivery not smooth

[KevinKilcourse]

My friends cousin is a professional rider in sweden (his name is Ludwig) and has a bike here in America for when he visits, but since he is only around for about a week a year he lets us use the bike for the rest of the time. We both have bikes of our own and have grown up riding, but this thing is just brutally fast. It appears that nothing is stock on the bike from the handle bars, triple clamp, clutch and brake levers, sprockets, chain, full RG3 suspension to the aftermarket clutch cover, shifter, bills pipe and silencer, to various other billet nuts and bolts littering the engine. We ride it on the road frequently, and love to open it up as often as possible, and have never had any reliability problems. However, since the first day we rode this bike it has always had this problem: The bike pops under acceleration and does not accelerate smoothly at all. It is almost as if during acceleration the power cuts on and off very briefly until it hits the power band, and then this thing takes off like nothing I have ever ridden before. we clocked it along side my friends audi at 90MPH possibly more going up a very long and very gradual hill by our house. So keep in mind that it does run well besides this problem. I would just love to feel the acceleration this bike is capable of without the blips in power delivery under acceleration. Any advice is welcome, and thanks for reading this whole thing.

 

[julien_d]

Something like that is going to be really hard to diagnose without riding it. Most all 2 stroke race bikes have a tendency to sputter a bit on the low end, particularly when cruising. The amount of this "sputter" is subject to interpretation by the rider, and whomever may be diagnosing issues with the bike. So it's quite difficult for a person who has no personal experience with this bike to diagnose anything. He/she might point you to any one of many different possible problem areas. Just a sort of disclaimer, I guess....

2 strokes are funny machines. If you tune one out for wicked top end, top end is gonna be where it's at on that bike. If it's behaved this way since it was new, and it's as trick as you say, it's probably just the characteristics of that engine. If you still suspect otherwise, you should probably start at the beginning and make sure the jetting is spot on. And I mean perfect...

What does your friends cousin Ludwig think about the way this bike runs?

J.

 

[2strokesrock]

I have no idea what it could be, so im just throwing this out there! Are you running high octane gas? could it be a pre ignition problem?