Honda Supra GTR150 2020 Owner's Manual page 73

Drive Chain Adjusting the Drive Chain Slack
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Checking the Drive Chain Wear
If the drive chain slack is excessive when the
rear axle is moved to the furthest limit of
adjustment, the drive chain is worn and must
be replaced.
Chain: FSCM428H or KMC428HG
If necessary have the drive chain replaced by
your dealer.
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