Adjusting Disk Brakes

[Bman]

I've tried my best, but its still winding me up.

My new XCR is brilliant. But I cannot get the disc brakes perfect.
It has Avid Juicy 3 hydraulic brakes on Alex DP20 rims. Before and after each ride I have been struggling to get the brakes to stop rubbing.

They only rub part way of the wheel/disc rotation. Reading up on it, some suggest loosening the calipers, clamping the disc then tightening the calipers again. This worked a little, so I have much less resistance than when Halfords first assembled it. Last night I thought I had the front disc/calipers perfectly aligned so there was no rubbing. Until I went out on it. Now it just "sings" at speeds of 20mph or more . The rear calipers still rub.

I've found that this is because the discs are not perfectly true. So wherever I place the calipers, it will rub on one pad or the other.

So, Do I just place them in a position where the least amount of rubbing occurs and wait for the pads to wear down a bit? Or is there a better solution?

 

[bonj2]

I experienced that with avids and tried everything in the book to stop them making that horrible grinding noise, but they still did it for all the months i had them.. The eventual solution was to switch to formulas, they are brilliant.
They virtually never rub, only a bit when i've just changed the pads and even then it's not very noisy, they soon bed in and run smoothly.
Much easier to change the pads than avids as well.

All brakes will make a bit of a noise when wet/muddy, but avids do all the time.

Change to formula oro or hope.

 

[Mr Pig]

All brakes will make a bit of a noise when wet/muddy, but avids do all the time.

I had a set of Shimano brakes that squealed. After much messing about I complained to Shimano and they sent me new set of brakes. The new brakes, despite being almost identical to the first ones, make no noise at all, ever.

A decent shop should be able to set the brakes up for you. There is no reason to put up with noisy brakes.

 

[Steve Austin]

your discs are warped. just bend them a bit, so they stop singing to ya

its easy to do, just use the jaws of an adjustable spanner

 

[Cubist]

your discs are warped. just bend them a bit, so they stop singing to ya

its easy to do, just use the jaws of an adjustable spanner

Or your fingers..... Avids do take some setting up and bedding in, my Hybrid has Elixirs, and they drove me absolutely mad for the first few rides.

 

[Renard]

Loosen the bolts on the caliper then pull the brake on as hard as you can and tighten the bolts while still hanging onto the brake.

 

[Bigtwin]

I've got two disc bikes - M4s and Julies.

The former are just great - no problems, all's as it should be etc.

The Julies are a total pain in the ass. Take ages to set up, and they drift out in storage, do different things at different times on a ride, the lot. Done everything to them - changed rotas, pads, Royal Blood (at great expense), even the front (worst) caliper - still rubbish.

I think some just don't ever want to play.

 

[02GF74]

depending on how much disc run-out (techical turn for sdie to side movemnt of disc as it rotats) you have, you may never get them to not rub on the pads if the distance between the pads is less than the run out.

you can ubolt the discs, move them round one slot and try again - if the hub is not machined perfectly or the disc are warped, this may change the run -out.

some calipers are fitted using shim - very thin washers - whereas others have slotted holes for adjustment.

where in herts are you - I could take a look if not too far away.