Help adjusting Shimano SLX disc brakes

[RhythMick]

Bought a second hand Yeti Arc recently with these brakes fitted. It's not had a lot of miles on the bike since build apparently, perhaps 300 mostly commuting with 1 decent MTB ride.

Both front and back brakes catch slightly on the disc. From the manuals, research and YouTube it would seem that adjusting these should be an absolute doddle. Loosen the top and bottom hex bolts, squeeze brake, tighten. Still catching, not a lot but enough to slow the wheel down if I spin it.

These are my first hydraulic disc brakes so I'm reluctant to do too much without making sure I get all the help I can. I'm thinking maybe one of the pistons isn't returning properly. Perhaps the spring clip is weak ? Perhaps I need to take out the pads, carefully push back the pistons, clean down with rubbing alcohol ?

All hints, tips and advice much appreciated.

 

[Pauluk]

Took me a while to get my cable ones set up correctly. If your mounts are similar to mine I would try just loosening just the top bolts that fix the caliper to the adapter, then holding the caliper central by eye tighten the top bolts. You can also tighten the top bolts while holding the brake lever but I don't bother as I don't find this so successful.
I also find that refitting the wheels makes a slight difference and I use this method as well as it can make a tiny difference to the disc alignment through the caliper.
Its a bit of trial and error, but once mine are set, they are good for a long while. I think its just practice to be honest.

 

[RhythMick]

Ok thanks will give that a go

 

[2Loose]

Instead of just loosening the bolts and squeezing the brake and then re-tightening,
Squeeze brake, spin wheel, repeat, repeat and then re-tighten. This will give the caliper a better chance of re-centering on the disk.

 

[RhythMick]

Thanks all.

I took the pads and spring out to find a small lip at the top of one of the pads. Can't have been more than 1mm but obviously the pad not inserted fully. Carefully ground it down, there's plenty of wear left on the pads. Pushed all the way back and adjusted, seems better now.