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Hi,
Hopefully a quick question - I have deore brakes on a bike and the pads aren't retracting sufficiently so the pad are rubbing the discs. Its not one side or the other side that isn't retracting - both pads are evenly rubbing the disc. I don't think the positioning of the caliper is at fault.
I've tried popping the wheel out, pulling the lever so the pistons extend out and levering them back followed by a good bleed which made little difference.
Is it worth trying this a couple more times? Does the fact that both pistons are equally rubbing the disc suggest it is an issue at the lever end?
Any other suggestions?
Incidentally, the brakes are ~5 years old and have been left untouched for about 18 months.
Are you using the little block to hold the pistons in when you bleed. Might have over-filled the system otherwise?
TBH I’ve had this before and a decent ride seems to fix it.
Ah. No I didn't. Not even sure I know where it is? I bled it with the wheel in. Might this have cause the problem? Do you happen to know how thick the spacer is? I can make one up out of something.
We did take it out for a few miles with a little rubbing but no change.
You've left your bike untouched for 18 months?
I've had this with the older Deore brakes. I squirted GT85 on the pistons (with the pads removed obviously) and then pumped them in and out a few times and then cleaned it all up.
🙂 I bought an Anthem and rode that instead. My old HT has been broken up to provide bits for my sons new bike. Another 24" wheel Specialised Hotrock build which I'm really chuffed with (albeit with a rubbing brake!).
Thanks oldnpastit - another thing to try tomorrow evening.
Do you happen to know how thick the spacer is?
I don’t sorry, but in place it holds the pistons flush with the body of the calipers, I’ve used a coupe of 2p coins in the past in its place.
Have a look on epic bleed kits website, they suggest layering up sheets of plastic, like old credit cards etc, they will sell you a kit too. I think I used a bit of plywood once, I'd guess 9mm
Try cleaning the pistons - carefully pump the brakes to get them as far out as you dare (without popping them out completely) and clean around the sides with meths or something similar. Push them back in and repeat a few times to fetch more dirt out of the gap between the piston and caliper.
If you can push both pistons flush with the caliper body at the same time then the amount of oil is OK.
Well - I tried cleaning the pistons with a bit of WD40 and it is a lot better but not perfect. I'll do it again when I get two mins and I'm sure it'll fix it.
Thanks for the advice!
I'd use brake fluid or silicon lube on the seals not wd40 and the like.
Pump them out as far as you dare, give them a wipe off and apply the fluid/silicon and work in and out a few times.
Having said that I had some new Deores a couple of years or so ago that were faulty from new and were working unevenly. I tried the above but it didn't work and they replaced under warranty. Replacements were fine.