I’m running a pair of tech 2’s and went to the bike yesterday and realised by rear brake was not working, on closer inspection it became clear that one of the pistons was not moving freely/at all and just wondered if anyone out there had any tips on freeing the piston up? It’s quite difficult IMO to get to the piston as the caliper is a sealed unit, I have been told to use some type of lubricant around the edge of the piston and then work that into the piston by squeezing the brake lever but as a said IMO it’s very difficult to get in there and the piston don’t seem to want to move!!!!

Any one else had this issue and any help appreciated…

I made a short U shape out of steel strip, take the pads out and fit the U shape in so that the back of the U is against the piston that’s NOT jammed. The open side of the U allows the jammed piston to move – when the other piston is locked in place, lever pressure will move the jammed one. Either work it in and out (I might put a simdge of silcon lube on the piston before I push it back in), or push it all the way out and clean it up before putting it back.

Get a cotton bud dipped in brake oil (dot 5.1) and wipe it around the sides of the piston sticking out, then with old pads in place use a flat bladed screwdriver (in between the pads) to push the piston back in. Just like when fitting new pads. Could be dirt has got into the seal and stopping it returning. May need to carry out a brake bleed, worse case change pistons and seals.

Thanks people will see what a can sort out when a get chance sometime this week…..but some good tips there!!