Analysis Of Motorcycle Troubles; Analysis Of Engine Trouble; Analysis Of Poor Idle Speed Of Engine - ZONGSHEN ZS250GY-3(EFI) Maintenance Manual

No idle speed of engine
Check the compressing
pressure of cylinder.
The comprssing
The comprssing
pressure of cylin-
pressure of cylin-
der is not enough.
der is normal.
[1]Check whether the outer connection part of
engine has leakage.
[2]Check whether valve timing is normal.
[3]Check whether the valve clearance is too narrow.
[4]Check whether the seal between valve and valve
seat is good.
[5]Check whether the piston ring is broken off or
dead or has poor elasticity.
[6]Check the abrasion of piston ring and cylinder.
56
Chapter 5

Analysis of Motorcycle Troubles

Section 1

Analysis of Engine Trouble

1.1

Analysis of Poor Idle Speed of Engine

Pull the valve of with hands
and check whether it is com-
pletely closed.
Yes
Shut off ignition
switch and hold for
10s of downtime,
then restart switch
when idling stepping
motor returns.
Check air passage of
throttle valve
Air passage has carbon depo-
sition seriously.
There is no idling output after
cleaning.
Check it by using fault di-
agnosis tester.
poor idle speed of
engine
The idle speed of en-
gine is too high.
No
Check whether the steel wire of
throttle control cable can be flex-
ibly pulled outside the cover of
cable and whether valve spring is
too soft.
Check by fault diagnosis
tester if idling is still high.
Check whether the elec-
trode clearance of spark
plug is too small.
Clean the passage.
The idle speed of en-
gine is unstable.
Check whether engine ignition is
timing.
Check it by fault diagnosis tester.
Y e s
[1]Check whether the CDI de-
vice has problems.
[2]Check whether the flywheel
of generator and the triggering
coil are loose.
No
Check the mixed ratio of combus-
tible mixed gas.
Y e s
Adjust electrode
clearance.
No