Honda CB650F 2018 Owner's Manual page 79

Drive Chain Adjusting the Drive Chain Slack
u
#
Checking the Drive Chain Wear
Check the chain wear label when adjusting
the drive chain. If the index mark on the
adjusting plate enters the red zone on the
label after the chain has been adjusted to the
proper slack, the chain is excessively worn
and must be replaced.
Chain:
DID 525V11 or RK 525KRW
If necessary have the drive chain replaced by
your dealer.
Red zone
Index mark
75