Hi,

I just bought a 2005 YFZ 450 with a whitebrothers slip-on and the air box lid is removed with an aftermarket air filter. It also has a jet kit in it, but i don't know what size the jets are. It's not running the way i would like, even after changing the plug, cleaning the filter, and messing with the air fuel screw, so i'm going to clean the carb and put the correct size jets in.

My question is, what size jets sould I buy? I don't intend to race the atv, I mainly stick to tight trail riding at lower rpms.

The two atv shops around my house would not answer any of my questions. They wanted me to bring the bike in, so they could bend me over with labor charges.

thanks,

 

I would try to get a repair manual for it....you'll be glad you did. I know the Clymer manual has jetting in their tables at the end of the chapter.

 

okay, I'll try that. I assume a clymer manual can be bought at a bike shop?

 

themotorbookstore.com should have it..

 

find out what size of jet is in now and find out what is stock. aftermarket pipe and open filter usually requires jetting. Move clip on needle up or down and if no better, then I would try jets a few sizes smaller and a few bigger. Call Hetricks racing and they will give you a few ideas.