Brake Caliper - Speedfight?

[boxer]

I'm servicing a Peugeot Speedfight for a friends son. The front brake is poor - it's a single disc set-up with the caliper having two pistons, one of which moves much more than the other.

Does anyone know wether this imbalance in distance moved by each piston is normal or is it a sign one piston is seizing?

I find it a little hard to believe they're this bad as normal but, to be honest, I wouldn't really know. The rear drums far better.

4k on the clock, but I'm sure much of the front end was replaced with 2nd hand parts when it was stolen/recovered.

Thanks.

Russ.

 

[welder8uk]

The fact that one piston is moving more than the other isnt a problem in itself - all it shows is that one piston has more friction than the other. However you need to make sure that the neaither piston is stuck/ seized, just pump them both out (may need to use a clamp/ block of wood to hold one in). You should be able to push them back in with your fingers.

If the brakes are crap, it could be one of the following:

- pads are naff
- pads not connecting with the disc correctly
- disc is naff (scored, bent - although not that likely if the rider
hasnt commented on it and he would know about it)
- may be air in system
- master cylinder may be passing oil - ie the seals are u/s
- hoses may be old and expanding

Most likely naff pads/ air in the sytem/ master cylinder wanting new seals. The fact that it has 2nd hand bits on shouldnt be a problem if they are fitted correctly and operate correctly.

there are a hostof things to look at with brakes that can cause problems, some important some not so important.

i am sure some one will point outanything else that is worth looking at.

Steve