KS Motorcycles K-LIGHT125, Maintenance Manual

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Fault diagnostic procedure for insufficient power of engine
Yes No
The power of engine is
insufficient
Support the main parking frame to make the wheels
off the ground and rotate the wheels by hands
The wheels can be
rotated smoothly
The wheels can not
be rotated flexibly
Check tire pressure 1. Check whether the brake is
stuck
2. Check wheel bearings for
excessive wear or damage
3. Check whether the spacer bush
in the hub is missing or too
short
The pressure
is too low
The pressure
is normal
Check whether the tire valve
core leaks and tires are
punctured or broken
Remove the spark plug, plug the threaded hole
of spark plug with fingers, then press the start
button or stamp down the start lever
You can feel that gas is rushing
outwards using your fingers and it is
purring
You can not feel that gas is rushing
outwards using your fingers
The compression pressure of
cylinder is normal
The compression pressure of
cylinder is insufficient
1. Check for air leakage at the joint
outside the engine
2. Check whether gas distribution is
conducted in correct time
3. Check whether the valve clearance
is too small
4. Check whether the seal between
valve and valve seat is good
5. Check whether the piston ring is
broken or stuck in the ring groove
or in lack of elasticity
6. Check the wear of piston ring and
cylinder
Start the engine, slowly increase the
throttle,and observe the changes in the
engine speed
The engine speed can increase with the
increase of throttle
The engine speed cannot increase with the
increase of throttle
Check whether engine ignition is conducted in
correct time using ignition timing meter
1. Check whether the clutch is slipping
2. Check the drive belt for excessive
wear
3. Check whether the centrifugal roller of
drive pulley is worn excessively
4. Check whether the conical surfaces of
driving wheel and moving friction
wheel are excessively worn or worn
into grooves
5. Check whether the conical surfaces of
driven wheel or moving driven wheel
are excessively worn or worn into
grooves
6. Check whether the rolling path on the
inner end surface of moving friction
wheel for excessive wear or pits due to
squeezing
1. Check whether the fuel supply system
is running smoothly
2. Check whether throttle, air filter and
exhaust muffler are blocked
3. Check whether the vacuum
diaphragm of plunger valve on
throttle body is cracked or damaged
4. Check whether the throttle float
height is improper
1. Check whether there
is fault in the ECU
ignition device
2. Check whether the
alternator flywheel
and trigger coil are
loosened
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