Honda CRF250F Owner's Manual Installation And Operation page 192

DRIVE CHAIN
Refer to the Safety Precautions on page 43.
The service life of the drive chain (1) is
dependent upon proper lubrication and
adjustment. Poor maintenance can cause
premature wear or damage to the drive
chain and sprockets.
The drive chain should be checked,
adjusted and lubricated as part of the Pre-
ride Inspection (page 32). Under severe
usage, or when the motorcycle is ridden in
unusually dusty or muddy areas, more
frequent maintenance will be necessary.
Inspection:
1. Turn the engine off, raise the rear wheel
off the ground by placing a support
under the engine, and shift the
transmission into neutral.
2. Check slack in the lower drive chain run
midway between the sprockets.
Drive chain slack should be adjusted to
allow the following vertical movement
by hand:
30—40 mm (1.2—1.6 in)
3. Roll the motorcycle forward. Stop.
Check the drive chain slack. Repeat this
procedure several times. Drive chain
slack should remain constant. If the
chain is slack only in certain sections,
some links are kinked and binding.
Binding and kinking can frequently be
eliminated by lubrication.
Excessive chain slack may allow the drive
chain to damage the engine cases.
(1)
(1) Drive chain
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