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Following a week of riding in the lakes and then scotland I was having a tinker with the bike to check everything was ok and noticed that I have some uneven pad wear on the rear disc brake.
When I say uneven I mean 1 pad has work approx 60-70% whereas the other pad is only approx 10-20% worn. Have I managed to set this up incorrectly?
Next thing is then what shall I do from here? Fit new pads? Run current pads as they are?
Brakes are 2009 SLX.
Misaligned caliper or unequal piston push.
If it works then leave it alone!
Shiamno aluminum Calipers have cheese thread so don't mess about too much.
You either buy new pads and realign the pistons by pussing in with the resv. cap off and also relaign the caliper with the disc with spacers etc.
Or
As from experience of the ****ers on here: take it apart and mess it up.
Or
Buy new pads and change the worn out pads when needed (a pal swaps one until the other is part worn etc.)
How would uneaqual piston push be resolved?
I had that prob with my xtr front (Swears)
I took out the pads as I felt the judder (I'm a picky ****er).
Then if you look down where the disc sits in the caliper (Where the pads and retaining pin rest).
Shimano XTR have grooved this section you can centre the disc caliper.
Once it's in the middle (near as possible with shims/spaceres/washers etc)
Then the caliper is spot on.
With the reservoir cap off, use a tyre lever to gently push the pistons back.
Now with new pads-pop in and and gently pump and the shimano auto centres.
Now that's 30 seconds of text that could lead to an hr of fettling or swearing.
If you're a newbie, then take out the pads, check the caliper centres over the disc. If so then leave alone. Remember the caliper has gentle threads if you have to realign.
Now that the pads are part worn-it'll never centre-so either buy new pads and centre the pistons.
If the pistons are sticky then it'll just happen again-but as they are new they should be fine.
I have a friend (yes I do!) who has left his caliper alone and swaps part worn pads when required.
I take my pads out when washing my bike (About once a year lol) so you could always do it again.
Just remember if the caliper is way off then the rotor is actually being pushed to one side to allow the pads to centre.
That uses more effort and creates more heat=minimal for some users but if you have a feel or OCD like me then you'll set it up right.
If you don't feel vibrations from the brake/noise when in a stand at home etc then it's really minimal and not worth doing.
Hope that helps?
Most ppl would leave it. Us detail picky sods would sort it but risk messing it all up.
Just use hand tight for the bolts and break/spin gently in a stand till you need to torque it up tightish (4-6Nm is not much for the threads to die).
If you use an adpater as in SLX and XT, LX etc for your caliper-loosen the caliper a bit, spin the wheel by hand and brake gently and retighten the caliper-but if the pads are unequal then this won't work.