330ex breaking up/knda missing

[tolson]

i can't seem to get my new 330 fst kit to stop breaking up at 1/2-3/4 throttle. starts right up, revs fines, breaks up under load. ive tryed 122-148 main, moving the needle, airbox on/off/holes. i just bought a high pro cdi thinking the cdi was bad. all those mods the same breaking up/ kinda missing happens.

as i acceralate, it kind of breaks up, sometimes kinda throttling through the breakup/missing. 1st and 2nd are bad, 3rd gets better.

i am at a total loss.
timing?
valves?
stator?
electrical?
carb fuel? i just totally ripped apart the carb and cleaned.

i had the entire motor apart and rebuild.

ALL I WANT FOR CHRISTMAS IS TO RIDE MY QUAD!!!!!!!!!!!

[hondardr4life]

I hav eno clue:confused: . It sounds like its time to call the pros. I would call FST and see what they think. I would call other shops/ dealers. Or if I got to the piont where I was about to throw my motor in the trash and buy a new one, I would take it to a daeler and say, "this is whats wrong with my quad, fix it" I just really hope I don't have this problem when I put my 330 together. Also, are you running an aftermarket cam? Becaause, this is just a wild guess, if you arent then the valves might not be staying open long enough to get all the fuel the much bigger piston needs??? LIke I said, thats just a guess.

[speedy400]

Sounds like either your jetting or your carb is dirty, make SURE you clean your carb and take everything apart in the process. This last summer my 416 was running just the same as your explaining, backfiring/ missing/breaking up. Put me out of riding for a month and 1/2.. turns out I had to fully dissessemble the FCR 3 times and clean it before it was finally fixed. Talk about a good way to piss someone off. good luck-darren

[Out_Sider]

sounds a bit like timing to me, but dont take my word on it

[tolson]

i have a mild web cam in it. maybe a racing will be better but, mickey said that i did not matter. timing might be the case, but it starts up and idles fine.

anyone else?

[hondardr4life]

Do you have the stage 2 web cam? Just wondering because thats the cam I am puttin in and I really hope I dotn have this kinda trouble with mine.

[dork]

if you can locate another carb to try, you could at least rule that out. are you getting good fuel supply from the petcock? no debris in the tank or plugged vent hose? check the spark plug wire for corrosion inside the boot where it threads on, coil connectors are tight&clean, and the plug itself. try the easy stuff first. from there it may be the stator.