KYMCO XCITING 500, Service Manual

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1
. GENERAL INFORMATION
1-23
XCITING 500
ENGINE LACKS POWER
c
Clogged air cleaner
d
Restricted fuel flow
e
Clogged fuel line between fuel
tank and carburetor
f
Clogged exhaust muffler
g
Faulty auto bystarter
h
Split carburetor vacuum piston
diaphragm
c
Faulty
ignition
unit
d
Faulty A.C. generator
c
Improper valve clearance
adjustment
d
Worn valve seat (valve stem too
protruding
c
Improper valve and seat contact
d
Worn cylinder and piston rings
e
Blown cylinder head gasket
f
Flaws in cylinder head
g
Improper valve timing
c
Clogged carburetor jets
c
Fouled spark plug
d
Incorrect heat range plug
c
Oil level too high
d
Oil level too low
e
Oil not changed
c
Clogged oil pipe
d
Faulty oil pump
c
Insufficient coolant
d
Faulty thermostat
e
Worn cylinder and piston rings
f
Mixture too lean
g
Poor quality fuel
h
Excessive carbon buildup in
combustion chamber
i
Ignition timing too early
j
Air in cooling system
c
Excessive carbon build-up in
combustion chamber
d
Poor quality fuel
e
Clutch slipping
f
Mixture too lean
g
Ignition timing too early
Start engine and
accelerate lightly for
observation
Inspection/Adjustment
Symptom
Probable Cause
Engine speed
increases
Correct timing
Engine speed does
not increase
sufficiently
Incorrect timing
Check ignition timing
(using a timing light)
Test cylinder compression
Check carburetor for
clogging
Rapidly accelerate or run
at high speed
Remove spark plug and
inspect
Check if engine overheats
Check valve clearance
Correct
Incorrect
Normal
compression
Abnormal
compression
Not Clogged
Clogged
Remove oil dipstick and
check oil level and condition
Remove cylinder head oil
pipe bolt and inspect
Engine overheats
Engine does not
overheats
Plug not fouled or
discolored Plug fouled or
discolored
Correct and not
contaminated
Incorrect or
contaminated
Valve train lubricated
properly
Valve train not
lubricated properly
Engine does not knock
Engine knocks