Disassembling The Front Brake Calipers; Checking The Front Brake Calipers; Assembling The Front Brake Calipers - Yamaha MTN850-A 2017 Service Manual

EAS30172
DISASSEMBLING THE FRONT BRAKE
CALIPERS
The following procedure applies to both of the
brake calipers.
1. Remove:
• Brake caliper pistons "1"
• Brake caliper piston dust seals "2"
• Brake caliper piston seals "3"
1
2
3
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a. Secure the right side brake caliper pistons
with a piece of wood "a".
b. Blow compressed air into the brake hose joint
opening "b" to force out the left side pistons
from the brake caliper.
EWA17060
WARNING
• Never try to pry out the brake caliper pis-
tons.
• Do not loosen the bolts "4".
a
c. Remove the brake caliper piston dust seals
and brake caliper piston seals.
d. Repeat the previous steps to force out the
right side pistons from the brake caliper.
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EAS30173

CHECKING THE FRONT BRAKE CALIPERS

The following procedure applies to both of the
brake calipers.
1
2
3
4
b
Recommended brake component
replacement schedule
Brake pads
Piston seals
Piston dust seals
Brake hoses
Brake fluid
1. Check:
• Brake caliper pistons "1"
Rust/scratches/wear  Replace the brake
caliper pistons.
• Brake caliper cylinders "2"
Scratches/wear  Replace the brake caliper
assembly.
• Brake caliper body "3"
Cracks/damage  Replace the brake caliper
assembly.
• Brake fluid delivery passages
(brake caliper body)
Obstruction  Blow out with compressed air.
EWA13611
WARNING
Whenever a brake caliper is disassembled,
replace the brake caliper piston dust seals
and brake caliper piston seals.
1
EAS30174
ASSEMBLING THE FRONT BRAKE
CALIPERS
EWA16560
WARNING
• Before installation, all internal brake com-
ponents should be cleaned and lubricated
with clean or new brake fluid.
• Never use solvents on internal brake com-
ponents as they will cause the brake caliper
piston dust seals and brake caliper piston
seals to swell and distort.
• Whenever a brake caliper is disassembled,
4-33
FRONT BRAKE
If necessary
Every two years
Every two years
Every four years
Every two years and
whenever the brake is
disassembled
3
2
1