My friend just bought a 2001 Raptor. It has a full Yosh. pipe, K&N, and jet kit. I dont know what size jet are in it. If you hold it at a steady rpm it cuts out and back fires. It also hesitates when your ridin it and you get on it. It idles good. I changed the sparkplug, put hightest gas in it, and drained the carb. But it steel dose it. Thanks

 

that sorda happen to mine sumtimes the rev limiter for reverse gets in the forward gears ...i jus shake around where my parking brake line goes into at and it works most of the time or under the front sprocket is a plug for the reverse limiter and if it comes off a lil bit it will do the same thing

 

Possible lean pop due to incorrect jetting or if it sat around awhile, pilot jets may be varnished & plugged due to bad gas. I've delt with both these problems on my 01' raptors