Binding Front Brake

[Peter]

Evening all.

The front brake on my AR is binding a little, you can turn the wheel whilst off the ground but it stops immediately. I have removed the pads which are fine and watched the pistons as they come out. The top one pumps out ok but the bottom one only comes out after the top one comes under resistance. The pads are wearing equal by the way. I have popped out both pistons and cleaned (not that they were dirty) reinstalled, bled but still have the same problem. Both pistons can be pushed back with your thumbs so nothing is seized, all looks like new. The bike has only covered 6400kms from new. Could it be the caliper seals. There are no leaks either.

Thanks in anticipation.

[fallenmikethebike]

How true is the disc?
Has someone had the front end apart recently, and reassembled the spacers incorrectly?
Mike

[Peter]

Thanksfor your reply.

No the disc is true and the spacer on the disc side and the speedo drive on the other side are fitted correctly. The bearings are fine and the wheel spins fine with no caliper fitted.

Do you think it could be the seals in the caliper not backing off as they should when the brake lever is released?

[twistednuts]

It sounds like the hose is goosed. If it is it wont let the pressure return, so once the brake is applied it stays on. My ford ezzy van once did it. I replaced everything, cost over 200 quid.

In the end it was a £11 brake hose!

Might not be this, but if its the original or even an old hose, then its worth a look at

[knackeredMk1]

It could be the seals sticking. Did you put a tiny smear of sillicon grease on them before you seated the pistons .

[fallenmikethebike]

Also, check the callipers pins are greased and sliding easily, these often fill up with crud.
Check that the pins are true, and not bent or corroded.
Mike

[Peter]

Thanks for all of your replies.

Mike you win the cigar, it was the pins partly seized, cleaned and regreased and now she spins like a good un. Many thanks for your advice.

Anyone notice or know why the pistons dont come out together?

[fallenmikethebike]

Move over big John, "Mike the brake", is the new kid in town .I have an old family heirloom clock, but it's only right twice a day, hasn't worked for years, but regular as clockwork it's right at 10.22 twice a day every day, just like that clock, if you posting the same answer long enough, sooner or later you will be right
Do you need the pistons right out?, if yes see the answer given to Fishtail earlier today.
Mike