Thumpstar ATV 125CC, Owner'S Manual

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137
IF YOUR ENGINE QUITS OR WON’T START
If you have a problem starting the engine or experience poor engine
performance the following information may help you. If you can’t correct
the problem, see or talk to your Thumpstar
Certified Motorcycle Mechan-
ic
.
r
Taking care of the Unexpected
SYMPTOM Engine starts, but runs poorly.
POSSIBLE CAUSE WHAT TO DO
idles roughly, too fast, stalls Check engine idle adjustment. Check fuel hose is not
blocked. If the problem persists, see or talk to your
Thumpstar
Certified Motorcycle Mechanic
.
runs erratically, misfires See or talk to your Thumpstar
Certified Motorcycle
Mechanic
.
blubbers (rich fuel mixture) See or talk to your Thumpstar Certified Motorcycle
Mechanic .
sooty exhaust (rich fuel
mixture) See or talk to your Thumpstar Certified Motorcycle
Mechanic .
detonates or pings under
load If applicable, switch to the recommended octane gasoline
or change your brand of gasoline. If the problem persists,
see your
Certified Motorcycle Mechanic .
after-fires (backfires) See or talk to your Thumpstar Certified Motorcycle
Mechanic .
pre-ignition (runs on after
ignition switched OFF) See or talk to your Thumpstar Certified Motorcycle
Mechanic .
SYMPTOM Fuel leaks from carburetor overflow
POSSIBLE CAUSE WHAT TO DO
float not adjusted right Remove carburetor and adjust float correctly
debris blocking fuel
shut-off valve Remove carburetor and clean the jet
SYMPTOM Does not start
POSSIBLE CAUSE WHAT TO DO
faulty kill switch Disconnect kill switch
no fuel Check carburetors getting fuel by removing drain screw
no spark Remove spark plug and do a spark test