1989 Honda FL400R Pilot Service Manual, Page 250Get this manual
TROUBLESHOOTING
ENGINE LACKS POWER
PROBABLE CAUSE
1Raise wheels off ground and spin
by hand WHEEL SPINS FREELY
2Check tire pressure with tire
WHEEL DOES NOT FREELY
Brake dragging Worn or damaged drum or knuckle
bearing
stuck parking brake
Incorrect parking brake adjustment
gauge PRESSURE NORMAL 3Lightly accelerate engine ENGINE STEED INCREASED
TIRE PRESSURE IS LOW
Punctured tire Faulty tire valve
ENGINE SPEED DOES INCREASE SUFFICIENTLY
Carburetor choke stuck opened Clogged air cleaner Restricted fuel flow Clogged fuel tank cap breather hole Clogged muffler
Incorrect float level Fuelair mixture too rich or lean
4Remove spark plug NOT FOULED OR DSICOLORED
FOULED OR
Spark plug not changed frequently