TROUBLESHOOTING GUIDE 145
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•
Cylinder h ead warped
•
Cylinder base gasket damage d
•
Reed valve damaged
Poor low-speed performance -
Spark weak:
•
Spark plug dirty, broken, or gap improperly ad-
justed
•
Spark plug cap or high-te nsion wiring de fe ctive
•
Spark plug cap shorted or not contacting properly
•
Sparkplugtypeincorrect
•
Igniter defective
•
Ignition coi
l defective
•
Stator damaged
Fuel/air mi
xture incorrect:
•
Idle adjusting screw improperly adjusted
•
Slow jet or air passage clogged
•
Air clean
er element clogged, poorly sealed, or not
installed
•
Starter plunger stuck open
•
Carburetor fuel level too high or too low
•
Fuel tank air vent obstructed
•
Carburetor holder loose
•
Air in
take duct loose
Compression low:
•
Spark plug loose
•
Cylinder head insufficiently tightened
•
Cylinder nut loose
•
Cy
linder or piston wo rn
•
Piston ring worn, weak, broken, or sticking
•
Piston ring side clea
rance excessive
•
Cylinder head gasket damaged
•
Cylinder head warped
•
Cylinder base gasket damaged
•
Reed valve damaged
KIPS ports stuck open:
•
KIPS exhaust valve stuck open (valve seized or
contaminated with carbon deposits)
•
KIPS exhaust v
alves assembled incorrectly
•
Exhaust advancer spring damaged
•
Exhaust valve operating rod seized
•
KIPSrodseizedincylinder
Other:
•
Igniter de
fective
•
Transm ission oil viscosity too high
•
Brake draggin g
Poor or no high-speed performance -
Firing incorrect:
•
Spark pl
ug dirty, damaged, or gap improperly ad-
justed
•
Spark plug cap or high-tension wiring defective
•
Spark
plug cap shorted or not contacting properly
•
Spark plug type incorrect
•
Igniter defective
•
Ignition coil defective
•
Stator damaged
Fuel/air mixture incorrect:
•
Main jet clogged or wrong s ize
•
Jet needle or needle jet worn