Moodyman
Legendary Member
I have Hydraulic disc brakes and the rear is rubbing.
But it only rubs down long fast hills where several stages of sharp braking may occur to manage speed.
About 200 metres after the braking stops, the disc stops rubbing.
There's no rubbing in the workstand or in normal travel incl. light braking at junction stops.
The braking surface on the rotor is very thin. Not measured it but it feels less than half that of the main body of the disc and considerably less than the front disc which doesn't rub.
Am I right in concluding that the rotor is too thin and therefore overheating (less metal) and warps during long descents which leads to rubbing, and returns to its normal position when it cools during pedalling.
I've done the usual checks - rotor is true, wheel sitting correctly in the dropouts and the pads have been removed and reinstalled after the pistons have been checked.
I might add the rotor has done c. 10k miles and I'm a heavy rider in a hilly area.
But it only rubs down long fast hills where several stages of sharp braking may occur to manage speed.
About 200 metres after the braking stops, the disc stops rubbing.
There's no rubbing in the workstand or in normal travel incl. light braking at junction stops.
The braking surface on the rotor is very thin. Not measured it but it feels less than half that of the main body of the disc and considerably less than the front disc which doesn't rub.
Am I right in concluding that the rotor is too thin and therefore overheating (less metal) and warps during long descents which leads to rubbing, and returns to its normal position when it cools during pedalling.
I've done the usual checks - rotor is true, wheel sitting correctly in the dropouts and the pads have been removed and reinstalled after the pistons have been checked.
I might add the rotor has done c. 10k miles and I'm a heavy rider in a hilly area.
