Surging 2000 CR250

[jshaw2628]

My 2000 CR250 sounds like its bogging when I first start it until it gets hot. After it gets good and warmed up it tends to surge when I decelerate and/or pull in the clutch. It is also starting a little harder than it used to. Does anyone have a clue? I just put in a new clutch basket, plates, piston and cleaned the power valve.

[FFRacing11x]

Sounds like you "possibly" have an air leak. Check around the base gasket and reedvalve area with carb clean or WD40 while the motor is running to see if the rpm changes.

[ossagp]

I am betting with FF on this one,,sometimes they will also idle up pretty high when they are warm and leaking. If you can make the idle go up or down by wiggling the clutch cable where it enters the case, you have a leaky ignition side crank seal failure. You may still have the leak even if that backwoods test there doesnt work.

[jer]

if you can't find a leak try a little ritcher setting on the carb.

[ossagp]

That is a good thought Jer,,,cooler weather might have caused the jetting req's to change. The thing with his clutch kind of reminded me of how my 88 cr acted about 15 years ago when the left side seal had gone bad. The clutch cable goes into the chamber that holds the ignition components as well as the crank seal,,wiggle that cable and the idle would go up or down,,pull the clutch in when you were coasting and the engine would rev up,,,it just gives air and extra path to the seal sometimes.

Taking the ignition cover off as it was idling made that one rev way up,,as it has others in the past too. For the last 15 years it has been one of the ways I looked for leaking crank seals.

[Faded]

T-dub/Andy,

Any quick and easy tips on how to get the ignition side seal out and the new one in? Seems I remeber hearing a few tricks but I cannot remeber them.

Thanks,
Andrew

[ossagp]

The seal comes out pretty fast for me with a small curved awl that i filed a bit on. Faster yet if I use the heat gun on it a minute.

I make the point slighly flat,,,and then on the back side of the curve I have another flat filed,,this lets the awl rock against the seal land at a better angle. They come right out for me.

[Faded]

Andy,

Thank you. I had planned on using some heat to convince it to come out. Someone told me to use a pipe spring puller, but I like your idea w/the awl better; I'll have to get me one and give it a try this weekend.

Thanks again,
Andrew

[darringer]

I have good luck screwing in a small self-tapping screw into the seal and using it as a handle to pull the seal out.

[monoshock]

I know you mentioned just putting a new piston in the bike, but how are your reeds? I'm assuming you checked them during the top end.