Argggh what is that noise? (V-brake related)

J1888

Über Member
Just got my Cannondale steed back from a new LBS (I'm moving north of the river...Thames).

Really nice chaps and and soon as I rode off back down south I noticed that the bike felt heaps better.

However, when applying the front brake it made the most godawful noise - not a squeaking sound, a loud, loud shrieking.

I tested the back and it was similar but not as bad.

Thought I'd let it warm up a few mile and keep applying pressure on quiet roads.

Back brake is now ok but front is just horrible. Rang the guys and they said they apply something to them that may be the problem but that it should go away, if not then take it back to them.

The noise only happens when pad hits the rim though which makes me think it isn't due to some degreaser etc.

Any ideas? Brake pad positioned incorrectly perhaps? The left from does seem a bit low...
 

steveindenmark

Legendary Member
Give the lbs a ring and see what they say. It could be that they just need bedding in a bit.
 

shouldbeinbed

Rollin' along
Location
Manchester way
Could be as simple as them not being toed in and not feeding solidly onto the rim without slap and squeal?

Check the pad is not catching the tyre when applied, that'd be bad in all sorts of ways.

Could it be very hard compound blocks taking time to scrub in?

Are they orientated and pressing evenly onto the rim? Extreme and unlikely but could misalignment somewhere (brakes or wheel not being bob on in the dropouts?) be pushing the tyre to catch a guard or stay?
 

RebornBumbler

Senior Member
Location
Barnstaple
Can anyone explain why "toeing-in" isn't nonsense (given that the pads will wear away almost instantly at the point of contact, and will be level with the rim soon thereafter?)

(BTW I'm not having a pop at you @cyberknight - I've seen plenty advice regarding the procedure, and used to do it myself until I considered what I was doing...)
 
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Hugh Manatee

Veteran
I always try to get my v brakes hitting the rim flat. I don't have any mountain bike with discs, instead I still use v and cantilever. The cantis I always toe in. The way I always did it was to place a match stick or 2mm Allen key to the rear of the block, gently apply the brake and then tighten everything up.

Squeal and judder was the result if this wasn't done. I seem to remember that Shimano (and the small companies who actually developed v brakes before the big S grabbed the idea) said the due to the linear pull nature of v brakes, toe in wasn't required.
 

RebornBumbler

Senior Member
Location
Barnstaple
... The cantis I always toe in. The way I always did it was to place a match stick or 2mm Allen key to the rear of the block, gently apply the brake and then tighten everything up. Squeal and judder was the result if this wasn't done.
I'm familiar with the technique - but how did your blocks remain toed-in after use (and therefore block wear)?

I seem to remember that Shimano (and the small companies who actually developed v brakes before the big S grabbed the idea) said the due to the linear pull nature of v brakes, toe in wasn't required.
I can't see how cable-pull / movement 'linearity' is relevant.
 

SpokeyDokey

64 and a little bit.
Moderator
I always try to get my v brakes hitting the rim flat. I don't have any mountain bike with discs, instead I still use v and cantilever. The cantis I always toe in. The way I always did it was to place a match stick or 2mm Allen key to the rear of the block, gently apply the brake and then tighten everything up.

Squeal and judder was the result if this wasn't done. I seem to remember that Shimano (and the small companies who actually developed v brakes before the big S grabbed the idea) said the due to the linear pull nature of v brakes, toe in wasn't required.
Same with my TRP CX9's - they are set up flat with Ashima 4 Function blocks and have zero squeal.
 
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