jetting crackling noise

[WickedATVer]

what does it mean if when you give it alot of gas and then let off really quick and it pops and crackles a little? a little lean or rich?

[mustang25]

It means its too lean...I dont know about you but i have a 2006 250ex..i put a pipe and airfilter on it...it started backfiring like crazy...after jetting it was fine...Any more questions, let me know...

[Wheelie]

The low speed/pilot circuit is lean.

[WickedATVer]

so its runnin lean some where. I'm its not a big deal I think its done it since i got it. Is just the pilot though cause I know it has a 170 dyno jet main but i don't think the pilot has been changed. these are the mods it has though k&N filter, UM high flow air box, white bros r4 full exhaust, and 426 bore/piston. I just wanted to know what i would have to do when I want to get the jetting right on. I'll get individual jets when I do it. what is the better jets to use keihn or dyno. I was gona get keihn, think i just need a pilot though?

[Wheelie]

Get a #42 Keihin pilot.