Avid juicy replacement brake

[GaryA]

My magura julie back brake caliper expired a fortnight ago. I bought a Avid juicy replacement from Merlin in thier bargain buys. Everything went fine on replacement but its taking a long time (60 ml so far) to bed in properly, drags slightly and it make a annoying scraping sound constantly. its also spongy and needs bleeding but I'm looking into how to bleed it properly (I've done lots M/cycle brake bleeding).

Should I have bought the avid disc to go with it or should that make no difference?

Yours in frustration

 

[subaqua]

you need to use the avid bleed kit too rather than a generic bleed kit.

have you centered the caliper on the rotor properly ? i know it might sound suck eggs sorry.

can't see it needing a avid disc but there may be minor variations which cause the dragging . the tech docs on the Avid website are fairly good for helping with the set up.

 

[Panter]

You definitely don't need the Avid disks but they should've bedded in by now.
Have you tried getting them really hot a couple of times? Seems to make a big difference IME

 

[User482]

If there's a scraping noise, it's probably the rotor rubbing the caliper body - you'll see it if you look carefully. Try centering it again. It shouldn't need bleeding from new - did you shorten the hose when you fitted it?

 

[GaryA]

Hi Folks ta for advice...Yes I centred the disc as per caliper installation instructions leaflet I will have to try it again. No hose shortning already bled (allegedly). Tried the trick of heavy elastic band around lever overnight- improved slightly but back to half-way-to-bars-before-biting in a few days. It also makes a awful grinding noise and vibration i can feel through the bars occasionally- but cant make it happen at will- very strange.
Come back V brakes, all is forgiven

 

[Panter]

That's very strange, I'm a huge fan of Avid brakes and have two MTB's built up with them, purely because they're so "fit and forget."
Maybe worth contacting Merlin? maybe the pads are faulty or contaminated?

 

[GilesM]

It maybe that you do really need the Avid disc as well, the problem is that the exact position and size of the pad in the orignal caliper will probably be slightly different to the set-up in the Avid caliper, the new pad could be on a section of worn and unworn disc, this would definately create vibration, it could also be that the outside diameter of the disc is not exactly the same for Avid and magura, is the outside diameter possbly making contact with the inside of the caliper, remember when braking things will flex a wee bit hence it may only make contact when braking hard. How far away from the disc are the pads when the brake lever is not pulled, if the pads are to far away, try removing the wheel and operate the brake a couple of times, it will bring the pads in closer, I have found that mtb hydraulic disc brakes don't self adjust quite like they do on car or motor bike hydraulic disc brakes.

 

[GaryA]

Thanks Giles, thats mekes sense..
Using it tonight but no time to mess on with it-will have to wait until the weekend.
Poxy work during week gets in way.