Pistons Check - Gilera Nordwest Workshop Manual

BRAKE CALLIPER
Removal
Place a clean container under the calliper, then disconnect the brake pipe.
Pay attention that brake fluid does not come in contact with painted parts.
Remove the calliper by loosening the securing screws to the fork (fig. 32) and
to the plate secured to the fork (fig. 33).
Remove the brake pads.
In order to facilitate the small pistons removal, blow compressed air into the
brake fluid inlet.
Check that the small pistons and the calliper are not damaged, in case,
replace.
In order to remove the piston oil seals, push towards the calliper inner side the
pistons oil seal.
By means of brake fluid, clean the piston grooves, paying attention to not dam-
age the piston sliding surfaces (on the calliper inner section).

Pistons check

Check that the pistons are not damaged (fig. 34).
Outer diameter (fig. 35) (section 1 technical data).
Allowable limit 0.05 mm.
Installation
Once removed, the pistons seals must always be replaced.
Prior to reassembly, moisten the oil seals using some brake fluid.
Install the pistons (pistons concave ends towards the pads).
Fit the protection rings, paying attention that they are housed on the calliper
grooves.
Fit the pads, pins and pad springs.
Fit the calliper on the disc, between the two pads.
Secure the calliper fixing screws to the fork with appropriate torque.
Fill the tank with DOT 4 brake fluid and bleed the hydraulic system.
DISC
Measure the brake disc thickness. Allowable wear limit 20% of the original
thickness (see technical data section 1).
Check the brake disc planarity (fig. 36).
Allowable oscillation limit: 0.15 mm.
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