[jet size?????] - ATV Riders Forums - Honda, Yamaha, Suzuki, Kawasaki, Polaris, CanAm, Arctic Cat, Kymco ATVs

Pages:1

jet size?????
(Click here to view the original thread with full colors/images)

Posted by: pauls400ex

i have a 2005 400ex and instead of just buying a jet kit and wasting money, wat size does the jet have to be because i'm going to pipe it and get k & n for it

Posted by: atvracer980

Rule of thumb, upgrade the exhaust and air filter- go up 2 sizes on the main jet, if its running a 142 main jet, 2 sizes would be in the ball park of a 148 main jet- the jets usually run in a 3 number spacing ie: 135, 138, 142, 145, 148 ect.- hope to help ya out.

Posted by: jsmith2232

I had a 146 dynojet main in mine with just afilter, revbox and pipe and it was perfect.