If you drilled the airbox at the same time it should be obvious. More air w/o rejetting for it=leaner condition. Leaner the mixture the more chance of popping. I'd add a shim at the least. Mains are already big enough for your setup i think. One shim to start, 2 if it still pops and check the performance as you go. Add a shim at a time till the performance no longer seems to benefit and stop there or even remove one. Or if you haven't already, try some more tapered needles like thruxtons. TBS are good too, but they're longer than thruxtons and longer than my stock 05' speddy so i had to shim them a lot to get richer. Depends on what bike you have. If it's an 05 speedy thruxtons would be the way to go with no shims. If it's a america of speedy older than 05 i'm not sure what the needles are like and therefore could say what to go with. But i can say that no matter what bike it is a set of thruxton needles should be fine because i have the same setup as you.....snork pulled, uni filter with hole drilled, and thruxtons worked fine. I did however find that TBS needles with two .5 mm shims and one thicker shim (approx .7-8mm) gave me slightly better midrange than the thurxtons while the thruxtons gave me better off the line accelleration but less of the midrange roll-on performance that the shimmed TBS gave.Of course these observations are based on the bike i have, so whatever you have may be react a bit differently.
But In any case i'd say definatly enrichen your needles however you do it.
Last edited by iknowjohnny; 12/31/2005 8:51 PM.
