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Cheese
08-26-2003, 10:11 AM
I have a 95 cr250 and just rebuilt the motor, everything but the crank. Its always hard to start, Im talking like 50 kicks. But once its warm it will fire up on the first kick. I cleaned the carb but Im starting to think that Im running to rich. My plug is always black with a thin layer of oil when I take it out. How do I find out what size jet I have. And what way do I go with the jet, down a size or up a size. Also I checked the spark and it has a nice blue spark and the compressions where its supposed to be. Thanks

Oh yeah, I cant get the bike to idle, well I can but it idles really high or else it will die. The bike also came out of georgia and I live in ohio.

groundfly
08-28-2003, 09:41 PM
here's all i know. hope it help's, some needle jet's are numbered for a flow rate, a larger # mean's more flow through a mid-range circuit. I'm pretty sure that number does'nt include the idle???? But some Jet Needle's have grooves and retaining rings, the top groove should give you the leanest setting, and the bottom should be the richest. this info is for a slide variable carb. not a fixed venturi...also check for a small air leak somewhere. I know this is all kinda sketchy and probably useless but it's what little i know.

groundfly
08-28-2003, 10:02 PM
oh yea..and check your idle adjustment screw. or your air and fuel mix screws. but you may only have one. If it's an air screw,clockwise is richer couterclockwise is leaner.....if it's an fuel screw, counterclockwise is richer, clockwise is leaner. you idle adjustment screw just moves your throttle slide up or down.