Buffalo Benelli Classica Series Instruction Manual page 30

NOTE: The gears can be changed when the pedals are turning. Very occasionally, the hub
may produce a harmless noise which is caused by its internal cogs and stop notches.
If you encounter resistance when turning the wheel, t he brake pads will need to be replaced
or the hub will need to be lubricated. This should be done by a professional bike workshop.
If the chain jumps off the sprockets when you are riding, the slack in the chain must be taken
up immediately.
If there is no further scope for adjustment, the sprockets and chain must be replaced.
Shimano Nexus 3 Speeds
Turn the twist-shift lever to select 1 of 3 gears. Level 1 is least resistance speed
Increasing pedal force (increasing resistance) indicator towards 3
Decreasing pedal force (decreasing resistance) indicator towards 1
These instructions on operation of the Shimano twist-
shift grips also apply for other makes of twist-shift
grips.
Adjusting Gears With Shimano Hub Gears
Set the REVO-SHIFT lever to 2
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