Shimano Hydraulic Disc Brake Problem

[rusky]

I have a problem with the rear brake on my MTB.

When I use it to slow on a descent, it gets jammed on. It must be heat related as it eases off when it cools.

The bike is quite new & I have changed the fluid & pads but no change.

Any thoughts?

 

[PeteXXX]

If it's quite new, surely your first port of call would be where you bought it from?

 

[rusky]

you're probably right but it was from Halfords & before anything is said, I had no choice - it was an insurance payout!

 

[rusty bearing]

Sounds like fluid expansion. What brake is it as we need to know if it's an open or closed system?

 

[rusky]

Shimano BR-M445

 

[rusty bearing]

Open system then. Expansion is allowed for in this system by a flexible rubber 'bladder' under the top cap. I would let a little fluid out of the bleed nipple, and I mean a little, push the pistons back fully and try it out. My old Shimano pair did used to rub a bit when they got really hot as I recall.