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ATC350X 85
12-06-2003, 10:07 PM
My '78 atc 90 will start to sputter in turns once ive ridden for about 20 minutes, it wont sputter if i keep the RPMS up but if theyre a little low it will start to sputter. It also pops a little out the exhaust. Also it will do the same things after i jump it. Also the seat for the float, should that have the springy side up or down, I dont remember, i have it with the springy side up, that maybe my problem, but not sure. I rebuilt the carb over the summer with a new kit and just recently started doing this. I am pretty hard on it, but its all for fun.

Teroy
12-06-2003, 10:13 PM
The point of the needle should be up into the carb and the "springy thing" should rest on your actual float. However your problem sounds points related or possibly valve.

ATC350X 85
12-06-2003, 10:21 PM
Yeah, but if i go in a straight line it doesnt sputter, only when i turn or jump, so i would think it has to be carb related.

Teroy
12-06-2003, 10:24 PM
Ahhhh, Yeah I would say your carb is loading up due to the needle not seating correctly.

ATC350X 85
12-06-2003, 10:28 PM
Oh, you know it does kinda sound like its doing that, I think i have the clip in the very first slot on the needle cause that thing runs very rich. It definitely gets rich when it bogs like that.

slippy4
12-07-2003, 02:21 PM
check for electrical problems, my 200x did this same thing, ran perfect for a month or so, then i was spinning doughnuts in the field and it sputtered a few times but ran perfect, then it progressivly got worse. it would run fine when in a strait line but as soon as you jump or turn it would run like crap,,, ended up being a couple of wires were bare (i dont think i ever taped them) and they worked there way to the frame and grounded themself out, then it lost spark untill it released itself from the frame.

ATC350X 85
12-07-2003, 10:55 PM
Ill take a look at that, thanks

ATC350X 85
12-08-2003, 09:42 PM
Im still thinkin its a carb issue, anyone know the factory settings? Its pissing me off.