Honda CRF230F 2004 Owner's Manual page 115

Drive Chain
LEFT SIDE
(6)
(6)
(5)
(2) chain slider
(3) chain guide slider
(4) chain roller
(5) lower slider
5. Replace the drive chain if chain slack is
excessive when the rear axle is moved to the
farthest limit of adjustment. Excessive slack
indicates the chain is worn beyond its service
limit.
106
Servicing Your Honda
(4) (2)
(3)
(7)
(6) cutouts
(7) wear inspection
window
To check the chain's service limit, measure
the distance between a span of
from pin center to pin center. If the distance
exceeds the service limit, the drive chain is
worn out and should be replaced.
Measure a span of 41 pins
New Chain: 25.0 in (635 mm)
Service Limit: 25.1 in (637 mm)
This motorcycle has a staked master link
drive chain which requires a special tool for
cutting and staking. Do not use an ordinary
master link with this chain.
41 pins,