popping backfire

[scrappyex]

my 400 ex has been runnin great . i let it set for a month and a half started it up and now it pops and backfires and wont idle at all. it only does it from 0 to qourter throttle ( popping ) to lean maybe or a clogged jet. please lend me some advice. Thanx all. RID"EM RED>










MODS: e-series slip-on,no lid,K&n filter w/ outerwears, WB rev box, stock needle position, no choke, 155 main, 42 pilot, AC nerfs about 1500-2000 ft elevation

[PunkA$$]

Pilot jet may be clogged. Try that first!

[mntly_imptnt]

^^sounds good
clean carb

[fastkid400]

yeah if its been sitting, just clean r up a bit

[scrappyex]

i cleaned the heck out of my carb and jets and it is still backfiring and at full throttle it sputters also

[PunkA$$]

Maybe try some fresh fuel and a spark plug?? If it's been sittin' that long.

[Screamin440]

Is there a gasket in between the carb and the intake that might have dried up? That would cause the idling problems and it running lean.

[PunkA$$]

Not sure if there's a gasket, but it's possible the clamps loose. Also make sure there's no exhaust leak!

[scrappyex]

i put new gas and a spark plug and it is still doing it. I'm tellin ya i'm really stumped on this one. it's like its cursed or somethin.