Just bought set of M4 brakes off of ebay, a Number 3 and a Number 8.
The Number 8 seems to be working fantastically, but i pulled the brake lever on the Number 3 once and now two of the pistons are stuck in the "on" position constantly...
I am new to hope brakes, what might be the cause of this and the potential remedy, at home if at all possible
James
Sticking pistons, probably just in need of a strip/clean and rebuild with some silicone grease.
as above, or dribble some brake fluid (or silicon grease/spray) on the pistons and work them backwards and forwards (using the lever and a screw driver) may sort em without the need for stripping them just yet.
See [url= http://steveukmtb.wordpress.com/hope-caliper-overhaul-minitrialsm4v2m6/ ]this guide[/url].
i will give that a go later when i get home,, before i have to take it all apart...as much as i want to at some point to fully understand where everything goes.. a friend of mine also said it could mean there is slightly too much fluid in the system?!?
a friend of mine also said it could mean there is slightly too much fluid in the system?!?
If it was over-filled, you wouldn't have been pumping the pistons out in the first place. If they can travel forward, they can travel back - assuming that the seals are doing their job. Over-filling would only cause the pistons to remain extended if the fluid were heated (from prolonged braking).
when you strip the caliper down, and remove all seals, they clean up very nicely in the dishwasher.
i have a number 6 caliper if you need it - pre-2010 boxxer mount.