jneiman My Rides (2) Posted March 31, 2010 I have an '04 RMZ250 with a Pro Circuit 496 exhaust and a dynojet kit installed - fuel screw turned out 1 3/4 turns. With a fresh spark plug, it starts really easy and runs really strong. But after a few hours of riding and cooling down over night, it just won't start until I put in a new plug. I'm hinking that that it's probably too rich and I'm trying to turn in the fuel screw a little at a time. Am I doing the right thing? Share this post Link to post Share on other sites
fender bender 59 Posted March 31, 2010 Sound to me as if your so rich that the air screw isn't going to be enough. Starting up has to do with the pilot jet and the plug fouling will be the main jet. If it was me I'd go two or three jets smaller on the main and try again. Be sure to take extra plug with you to ride. Share this post Link to post Share on other sites
jneiman My Rides (2) Posted March 31, 2010 Thanks I'll give it atry Share this post Link to post Share on other sites
jneiman My Rides (2) Posted April 6, 2010 After moving the needle down and going down in the main jet size, the bike runs great!! Share this post Link to post Share on other sites