Rapid & uneven brake pad wear...

parkinpants

Managed to wipe out some brand new sintered brake pads for Avid Elixr 7 (originals, not the Clark ones) in no time. After 70 miles (in mostly wet conditions)....

Rear pads - 1 side worn to the metal, other side has a bit of pad left at the bottom but gradually thins out to the bone metal (almost) at the top of pad

Front pads - much better than the rear, fair bit of pad left but one side noticeably more worn than the other

I do use rear more than front, and "disc rub" was noticeable for a lot of this time but something I've always had so something I've come to put up with. Anyway, I figure I should investigate the cause of this when I replace the pads. From what I've read up so far two popular causes:

1. Sticky piston.
2. Caliper not aligned over rotor

I've read a suggestion to...
- check rotors are true
- remove pads
- squeeze levers unti pistons meet rotor
- look out for any sign of a 'sticky piston'
- align rotor this way with pads missing (rather than using the loosen/squeeze/tighten method)
- if sticky piston showing, hold back good piston and force sticky one out, then clean it with mineral oil

Does that sound like a good plan?

cooldad

I nasty conditions I've wiped out a set doing a couple of runs down Whytes. So maybe 20 miles.

Although it sounds like you drag your brakes if the rear wears.

I wouldn't worry about the bike, work on technique.

The Rookie

Clean the exposed piston while the pads are out before fitting new ones, pump them out, then a small amount of brake fluid on a cotton bud round the piston, push it in, pump it out and clean off any muck, repeat if necessary and then carefully clean away all fluid before fitting new pads. But mostly this sounds like technique, the rear should never wear out first, correct braking uses the front mostly and you should either brake or not, dragging the brake for confidence barely slows you down and wrecks the brakes.

parkinpants

Sounds about right. I'll stop blaming my tools and learn how to ride properly then.

cheers

parkinpants

just replacing my pads now...

I squeezed the rear brake lever and only 1 piston was moving, 1 was stuck. I held the moving piston with a spanner and then squeezed which did get the other piston moving again.

I didn't get the change to investigate further or clean it up because 10 minutes outside is currently enough to make my hands freeze and I'm off for Sunday morning ride soon with or without sticky pistons.

The Rookie

It's normal when there is no resistance for just one to move, one will have a slightly lower resistance to moving and once it's moving will stay doing so, perfectly normal.