rear-brake, tech-advise needed

I have removed the rear-brake now completely. The manual says to push the pistons out with pressurized air. Has anyone ever come across another way ?

I noticed one of the pistons can be moved easily around, yet not pulled outside the caliper, the other seems to be stuck- I consider that not correct.

Thanks for any input.

Holger

I have found the easiest method for removing stuck caliper pistons is to use a grease gun connected to the caliper pressure feed - most calipers have an M10 fine banjo fitting which is compatible with grease gun fittings. It may be necessary to bolt the caliper back together and refit the freed piston - clamping this in place to ensure that it does move preferentially when you add grease gun pressure.
Its a bit messy to clean everything up afterwards but much safer than using compressed air!
 

wrote:

I have removed the rear-brake now completely. The manual says to push the pistons out with pressurized air. Has anyone ever come across another way ?

 

I find it's easiest to do while the caliper is still attached to it's hydraulic system.  Remove the brake pads and inserts a slat of wood that will allow the piston(s) to move, but prevent them from moving all the way out of their bores.  Use the brake pedal/lever to pump the pistons out.  Once the piston(s) are just about out of their bores, disconnect the hose.  You can 'strap' a hose clamp around the piston(with a strip of rubber or thin cardboard) and the hose clamp will give you something to pull on to pull the piston out.

just some feedback:

I manged to get them out by air in my company (with assistance of one of the guys working there). Cleaned everything, put everything back together. No parts surplus.
Pressurized the system/ got the air out and: it works. No hot break-disc anymore. Bike rolls perfect.

Just to add: I work in an office and I know where to move the mouse as well as which key to press on this keyboard so things get done or I can do them. Doing it with your own hands (successfully) feels great. 

Holger

wrote:

... No parts surplus.. ...

Holger

 

Always a positive sign.