Lateral Play Of The Connecting Rod; Checking The Runout Of The Crankshaft; Piston; End Gap - SHERCO 250 SE-R 2017 Workshop Manual

ENGINE COMPONENTS
❱❘ Lateral play of the connecting rod
- Measure the side clearance of the connecting
rod [A].
Side clearance of the connecting rod:
Standard: 0.8 mm - 1 mm
Permissible limit: 1.25 mm
If the clearance exceeds the permissible limit,
replace the crankshaft.
❱❘ Checking the runout of the
crankshaft
- Place the crankshaft in an alignment fixture or
a set of V blocks and then install a pair of dial
indicators as shown in the image.
- Slowly turn the crankshaft. The maximum
difference between
corresponds to the runout of the crankshaft.
Runout:
Standard: 0.03 mm maxi
Permissible limit: 0.05 mm
If the runout is not correct, replace the
crankshaft or align it so that it falls within the
permissible limits.
❱❘ Piston
If you want to use a piston that has already seen
service, then check the following:
- Skirt: Check for traces of seizing, slight traces
can be removed with a soft stone.
- Stuck rings: The rings must not be stuck in the
grooves. To clean the grooves you can use an
old ring or 400 grit sandpaper.
- Ring retainers, the ring retainers should be in
good shape, the rings should not turn in the
grooves.
- Piston rings: Check the condition and the end
gap.
❱❘ End gap
- Place the piston ring in the cylinder (use the
piston to push it approximately 10mm into the
cylinder).
- Using a feeler gauge measure the end gap.
End gap: 0.40 mm max
the measurements
A
A
A
25