[gorilla570]

Hey guys. i recently did a top end rebuild on a 2006 crf250r.it had a bad valve job done, the Exhaust valves have a small leak. which will be fixed for free by the shop that did it. but i also think that the idle isn't correct. we have gotten it to start by bump starting and it will run for maybe 20 seconds then die. today got it to start by kicking it. it ran for at least 4 revs of the engine. it would start to die sometimes when i would try and give it throttle. but at least it started is how I'm looking at it right now. should i try and make it richer? would that help the problem at all?

[JimDirt]

How long did it sit since the breakdown ?? , could be the pilot jet is clogged , is it popping a lot when you try to rev it mainly when you let off the gas ??

Have you checked the Hot Start at the carb , if it is stuck , it will lean out the motor

If it runs then dies , it could be the the float is stuck , as it sounds like its running out of gas

These are all things it "could" be , more detailed running and time frame info would help