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jtej
10-22-2003, 08:44 AM
a little background first. we traded a riding lawn mower for this 1993 300ex. the guy had spray painted the frame primer before we got it. we decided to paint the frame to make it look better. i took pics of the wiring and such, then proceeded to tear the quad down. I took the motor and set it on a 2x4 stand, and other parts in boxes, where it sat for about 6 months before i got around to putting it back together.

btw the quad had just been rebuild, with a high comp piston everything else is stock. it ran great before i tore it down.

we got the bike all back together wired up and started it up to make sure it ran. it idles fine, when you hit the gas it will go up to 1/4 throttle then it starts spitting and sputtering like it is hitting a rev limiter or something. i have a 93 300ex also so i switched the entire wiring harnesses. still the same problem, so it wasn't the wiring. i dropped the carb into the ultrasonic cleaner at home thinking it was the jets, prob. still remains, switched pipes, checked timing, throttle cable, etc... still the stuttering won't go away.

What is wrong with this poor quad??

Chanman420q
10-22-2003, 01:44 PM
sounds like jetting to me

dirtmomma
10-22-2003, 02:22 PM
Check your plug & the go from there sounds like jetting to me too. Mine did this over in Idaho this summer so we had to rejet big time, what are you running in it now??

jtej
10-22-2003, 02:42 PM
like i said it ran great before i took it apart. and everything as far as i know is bone stock with the exception of the high comp. piston. but the guy may have changed the jetting without us knowing. i may try getting some jets for it and experiment. i also took the carb off my bone stock 300ex and put on there and it didn't help it.

i guess i just have to keep experimenting.

ZSK
10-23-2003, 08:54 AM
This sounds odd but check your choke, it maybe stuck open. Mine will do this with the choke on. It will idle fine and go up to about 1/4 throttle and sputter.