[Closed] XT Brakes Problem

You've not fully bled them.

Mine do this when the pads get low. I know a couple of other people's who do the same.

Changing pads brings them back immediately

got my bike last may...havent bled them yet ? dunno how to actually...how often do they need bleeding..... must get me some new pads soon too...

I presume they are M775?

I have some on my bike, and the bite point does change when the pads are low as matthew_h says. For elaine anne, I read somewhere that they need bleeding at least once a year.

The brakes are pretty much new as are the pads so I don't think that could be it.
Any tips on bleeding them as I have tried the normal flushing fluid from the lever and also the injecting fluid into the caliper methods, neither getting rid of this problem.
They have also been very noisey lately even after centering the caliper so that there is no rubbing.

As you can see, I am not having much luck with them yet!

thanks toaster.. they wont need bleeding just yet then.....

Hi chrispy, my dad's were really noisy as well. He swapped the pads round, and it solved the problem. Also, try checking the rotor isn't distorted, as this caused the most annoying squeaking sound with mine.

cheers toaster, I'll give that a go tomorrow.

Bled once a year? I've got some Deores that are 5 years old, never bled and work perfectly. A sealed system using mineral oil should need next to no maintenance.

To the OP - are you letting the pistons out a little before/while bleeding? I had lots of problems with a set of XTRs when I was using the Shimano-supplied yellow blocks. Replacing these with something a bit thinner cured it.

Onion, I have been using the yellow blocks.
I'll try your suggestion tomorrow too. Do you push the pistons fully back before sealing the reservoir if you bleed the brake with a thinner block?

Thanks!

onion - Premier Member

Bled once a year? I've got some Deores that are 5 years old, never bled and work perfectly. A sealed system using mineral oil should need next to no maintenance.

It will not be as crucial to bleed shimanos annually as they use mineral oil which does not absorb water in the same way but you will still get a build up of muck in the system - particles dirt, bits of oil seals and alloy worn out of the system. I bet if you bleed thru those 5 yr old shimanos the fluid will be filthy

Chrispy - I push them back just far enough to get the pads and rotor to fit without rubbing.

TJ - why would I want to bleed them when they work perfectly?

Preventative measure.

[i]Preventative measure. [/i]

My take on disc brakes is that if they work, leave well alone! Just in the process of sorting my XT brakes, they've been plagued with sticky/lazy pistons for a while now but with the bike in bits, now is a good time to sort it all out.