[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: jamienlogan

I have a 440 with a 11:1 piston stage 2 cam and a t4 pipe. The company that the piston came from told me to run a 45 pilot and a 170 main. It starts fine and idles good so the pilot should be good, but it cuts out at full throttle, so do I need to come down on the main or what?

Posted by: 2004exrider

170 sounds a little lean maybe, im running a 165 right now and its perfect. But the only way to tell is to look and see what color the tip of the spark plug is.

Jimmy

Posted by: jamienlogan

I think I am 3 1/2 turns out on fuel air screw. What way is what for fuel and air?

Posted by: jak1389

quote:
Originally posted by jamienlogan
I think I am 3 1/2 turns out on fuel air screw. What way is what for fuel and air?

in is richen it up, out is to lean it out

Posted by: JOEX

quote:
Originally posted by jak1389
in is richen it up, out is to lean it out

I thought it was the other way around on the 400ex

Posted by: jak1389

quote:
Originally posted by JOEX
I thought it was the other way around on the 400ex

possibly? umm, hmmm

now i am confused also. i need to look it up i guess. and i will get back to ya

Posted by: 400exstud

Out is to richen it.

Is it "bogging" at wide open if you just stomp on it? If it is then the main jet is too rich.

Posted by: jamienlogan

just wide open

Posted by: jamienlogan

I need to come down then on the main right?

Posted by: 2004exrider

Try taking you airbox lid off and riding it, if it doesnt do it any more (or if its not as bad as before) then your running rich. If it still does it then your running lean. Best thing to do is check your spark plug though.
Black- Rich
white- lean
Dark grey-gold: Perfect!

Jimmy