bike quits when I touch the throttle

99 WR400. what could cause my bike to stall when I touch the throttle? I changed from yz timing back to wr and it starts fairly easy but, when I try to give it some throttle it keeps stalling. I pulled the carb apart recently and cleaned hell out of it. I keep thinking I smell "bad" gas now and then also. Could this be a possibility? Where should I start looking?

Edited by treefrog

Make sure the gas tank is clean, and you have quality gas on there. Sounds like your carb won't transition from your idle to pilot... Smaller pilot? Have you tuned the air or fuel screw?

Are you sure there is a clip on the needle?

I just cleaned the carb. Needle clip#3 still there. Will pull carb, clean,and replace pilot. Going to drain and clean the fuel tank also. Will update with results. Hopefully good results.

It's not the pilot, or it wouldn't idle.


It's more likely the air jet in the intake bell, clogged with schmutz..... or your main jet fell out....

Edited by TheKoolAidMadeMeSick

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