So I thought I'd try and sort out my XTR rear brake which has been rubbing for a while. I pushed the pistons back in no problem, re fitted the pads and wheel but now it's as if there's no pressure in the system. One piston moves slightly but the other not at all.

Please does anyone have any ideas what the problem might be as apart from the rubbing they were working fine up til now.

Sounds like it needs bleeding. How does the lever feel – is it still firm or does it pull back to the bars?

Check the fluid level in the reservoir. Top up as necessary, pump the lever a few times and then zip tie the levers back to the bar over night. Should sort it without having to fully bleed them.

Did you do this with the bike upside down? That can sometimes introduce air into the system. With the bike the right way up push the pistons right back and then pump the lever a few times – if there is a bubble of air near the lever end that might just push it back into the reservoir. Otherwise a full bleed thru

The bike was upside down so I'll have another go. There seemed to be plenty of fluid in the reservoir but might be a bit less now and the lever pulled right back to the bars 😐

Think I might invest in a bleed kit and see if that sorts it

So if I get one of these is fairly straght forward?

If they worked fine before then a full bleed is probably not neccessary. Just zip tie the levers back like I said, leave over night and bingo.