My friend just bought a used 2004 yfz 450 it doesnt have a whole lot of hours and its all stock... when he starts it or just stops and puts it in nuetral or just pulls in the clutch it revs up real high. a not normal idle speed but if u pull the choke and push it back in it goes to its normal idle speed but as soon as u touch the gas it speeds way up again. does someone know what to adjust or what the problem is thank you




Shoulda went with the preddy

 

thats cause they like to be ridin ***** to the wall no jk i dont know wish i could help

 

Have him check his jetting-could be running lean.

 

What should the right jetting be for just straight up stock.

 

I would just buy the GYTR jet kit, it comes with a better needle and an assortment of jets. Or just get a 45 pilot and a 165 main and try that. If it has the stock jetting it comes to lean from the factory and won't idle well when cold