I have a 04 rmz 250. Port and polish, high compression piston running 110 octane, hot cams stage 1, boysen quick shot, boysen power wing. All brand new on a build didn’t even check the jets yet but the bike takes forever to start then it won’t idle at all but seem good on the high end I’m just looking for some rough jet setting to get me close so I can dial in

 

Well with the amount of upgraded parts and race fuel I will go ahead and tell you it doesn't surprise me at all that it has been difficult to start. I would almost be willing to bet that you would need to go up a couple sizes in your pilot jet. Another way to troubleshoot this issue would be to determine where at in the throttle you are able to maintain an idle, if it is at an 1/8 or less you could try lowering the clip on your throttle needle in turn raising the the throttle needle and possibly allowing this bike to idle correctly. I am almost certain the pilot jet is the culprit here though.

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