Chronic brake squeal with Avid Ultimates

[garethrl]

Hi folks,
Last night's _very_ noisy night ride had people lining up take shots at me by the end, so I'm looking for some advice.

I have the following setup: Avid Ultimate V's (and levers), XTR ceramic pads, Bontrager RaceLite ceramic rims. I've set about 1mm of toe-in the good ol' fashioned way, and the pads are set correctly relative to the rims and not fouling the tyre at all. However, I get chronic front brake squeal every time I use even moderate braking force. Heavy braking results in an eardrum shattering banshee-like wail and instant evacuation of all wildlife within a 1km radius. This only applies to the front BTW, no issues at all with the rear.

Is it something simple like the wrong pads for the rims, or needing more toe-in? I've noticed that I get quite a lot of fork dive when I brake so is there an way that that might contribute? I also noticed some play in the headset (SID World Cup 80mm, don't get me started on the carbon steerer!) and after I'd tightened it up that the problem got even worse!

Any thoughts and tips greatly appreciated. None-too radical solutions preferred since the braking performance is excellent!

Cheers, Gareth.

 

[jim-laden]

If I were you I'd give the rim and pads a good clean and look for imbeded debris in the pads. No scientific reasoning behind it but it may work.

Jim

 

[al]

Ceramic pads do tend to glaze over time! Scrub the pads up with some abrasive or just replace them.

I have had this problem in the past and it was just a bad combination of pad and rim. No matter what i did the squealing never got any better.
I think they were Rigidas and Avids!

Hope you cure it. I know how iritating it can be.

Cheers,Al

 

[al]

Just had a thought! :shock:

I have some ceramic pads somewhere. Give me your address and i will post them to you.

You never know, they could do the trick.

Cheers,Al

 

[Sithlord]

I came across this problem when I was doing a search on these brakes a few weeks ago, (I was going to purchase a set ) It seems a common problem with them, have a look on the web fella.. you'll see other people with the same problem, I cant remember the exact cause , but I think it was something down to the tight tolerances on this setup..

 

[syncrosfiend]

garethrl.....this was a common issue at our shop and avid sent us a whole box of pads to help.

step 1. do not toe in the pads. not on any v-brake. shimano, avid, campagnolo (yes, they make v-brakes), all advise against it.

step 2. replace the pads you have with a pad of a softer compound. the standard black compound pads from avid will work. so will WTB razor blades (not the dual compound), the blue or black ritchey logic pads, and most pads that are not from aztec, ebc, or kool stop.

step 3. make sure that all threaded fasteners are torqued to spec (this includes the brake bosses on the fork lowers).

step 4. clean the ceramic track with acetone. start fresh.



in some rare instances, avid replace the ultimate brake with a single digit 7 under warranty at no charge. weird but true.