pipe change

[4TraxRider]

I had my quad jetted in the winter, to run a pro-circuit t-4 with no airbox lid. I want to put my stock pipe back on for a while, with the airbox lid for a big trail ride were going on in PA. My quad sputters in the midrange no matter what I do, i richened the needle, same thing, i leaned the needle, same thing, it spudders at the same spot, just as bad nomatter what. Can someone tell me what way to go, richer or leaner. Thanks.

[Natertot426ex]

Find out what the stock jetting is and put that back into it. It should run then

[4TraxRider]

Won't work, I have a 406 overbore, no choke, and highflow headers so stock wouldn't really work, I just need to know if i should go richer or leaner. I think leaner, but it seems to get worse leaner.

[UglyMotha™]

just a shot here but i could be wrong but you said your running a highflow header and then you choking it off by putting the air box lid back on you probably have no back pressure just a hutch i dunno for sure but even still you should be able to run stock jetting on just a 406 bore i'm running a 158 with my mods, just put it in today i might be able to still go one size lower

[4TraxRider]

I've got the stock main jet back in, and it runs fine until about 1500rpm, then will spudder, and if it will rev to probably 6000-7000(guessing) it runs fine. Only in the midgange it spudders, not mattering how much throttle, it doesn't matter it it's wide open, or barely enough to get there, it spudders.