Yamaha 4SH-28199-67 Owner's Manual page 316

WARNING
Operating with improperly serviced or adjust-
ed brakes could cause loss of braking ability,
which could lead to an accident.
After servicing:
Make sure the brakes operate smoothly
and that the free play is correct.
Make sure the brakes do not drag.
Make sure the brakes are not spongy. All
air must be bled from the brake system.
Replacement of brake components requires
professional knowledge. These procedures
should be performed by a Yamaha dealer.
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