GPX 250r TSE, Maintenance Manual

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The engine has
abnormal noise
Check whether there is
abnormal noise in the
valve
Abnormal noise in the
valve
Valve clearance is too
large
Valve wear
Check whether there is
abnormal noise in the
cylinder
Cylinder has
abnormal noise
Piston and cylinder
wear
The small end holes
of the piston pin and
connecting rod are
worn
Crank pin and
connecting rod large
end wear
Check whether the
timing chain produces
abnormal noise
Abnormal noise in the
chain
Camshaft wear
Timing driven
sprocket wear
Timing chain
stretched
The timing chain
automatic tensioner
fails, or the guide
wheel is worn
Check whether the
driving gear and the
driven gear produce
abnormal noise
Abnormal noise in the
driving and driven
gears
Gear machining
accuracy is not enough
The gear teeth are
worn
The matching
clearance between the
driving and driven
gears is too small or
too large
SELECTION AND RATIO OF ENGINE OIL
In the process of engine work, the oil has the functions of lubrication, cooling, cleaning, rust
prevention, sealing and noise reduction. Compared with the four-stroke engine oil that only
lubricates and does not participate in the combustion, the two-stroke engine oil needs to be mixed
with gasoline and then be used as fuel. So, the fuel of two-stroke engine is also required to play a
lubricating role while participating in combustion.
The difference between two-stroke engine oil and four-stroke engine oil is as follows:
Item Two-stroke engine oil Four-stroke engine oil
Flash point [1] low, flammable high, flash point >200℃
Thinner Yes No