Is this a common thing?

I’ve been meaning to sort it for ages and I guess this current weather has reminded me it’s still a problem…

I’m unsure if a simple bleed will sort it or if I need a new lever? I hate bleeding brakes so don’t want to do it unless it’s the solution.

If I cool the lever down with a hosepipe it returns to normal for 10 mins or so. Tends to be ok in normal temperatures but this 30’c stuff is a problem!

They may have been overfilled. I would try opening the bleed port in the lever and then use a flat bladed screwdriver to wedge the pads apart. This will push the pistons back into the calipers and eject any excess fluid or air from the reservoir.

I’m in Australia and ridden many times in hotter weather. No heat related issues with my XT M8000 brakes so I’d guess that it’s something other than the heat.

I know, I have two brakes and the front one is ok! Whatever the problem is with the rear brake it’s the heat that then causes it to lock on. I’ll try a bleed

more than likely as above, been overfilled at some point. I had the same with my old Hope brakes a few weeks ago.

I’ve had this problem on previous gen XTs.

I believe it was the seals swelling in the heat causing excessive friction on the push rods. I only had it when the bike was left in the sun, never happened riding along though. I think its more of a design issue rather than bleeding etc.

A few years ago, set out on a big ride. Stopped at a pub for dinner and left the bike in the hot sun. I’d noticed a problem with the brakes earlier on but not enough to stop me.

When I went to start my ride again brakes were binding. Had to disconnect them to let oil out so I could ride home, luckily up hill.

When I stripped them, the seals inside the levers were covered in dirt and I think they had too much friction. I cleaned them and put them back together but it did it again.

There’s a big thread on it on here somewhere.

Unfortunately, as they are shimano, I think you need to replace the levers.