Screaming brake blocks

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JC4LAB

Screaming brake blocks

Postby JC4LAB » 11 May 2009, 9:36am

Bought a second hand galaxy hardly used but the rear brakes scream so loud.(never haerd anything as loud before).Can anything done DIY before I take to a shop and leave it to the experts? There may be a very very very minute buckle though...

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Mick F
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Re: Screaming brake blocks

Postby Mick F » 11 May 2009, 10:07am

There are all sorts of cures for squealing brakes, but before you do anything else, take off the back wheel and thoroughly clean the rim. I do this with the kitchen sink with v hot water and washing-up liquid. Scrub the brake surface with brush or soft pad, then rinse off and dry.

Also, remove the blocks and shove them in the soapy water and give them a scrub too.

Basically, oil and muck solidifies on the rim and blocks sometimes, and creates a squeal.

Re-assemble, adjust the brakes as normal, and try again.
Mick F. Cornwall

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lauriematt
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Re: Screaming brake blocks

Postby lauriematt » 11 May 2009, 10:54am

'toeing' the brake pads in can reduce squealing...by that i mean you set the pads at an angle to the rim - instead of rubbing on the rims square on.

link - http://www.utahmountainbiking.com/fix/brakepad.htm
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PW
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Re: Screaming brake blocks

Postby PW » 11 May 2009, 11:40am

If the brakes are cantis strip them down, clean everything until spotless, re-grease - give it plenty - and re-assemble. It often turns out to be the brake arms vibrating on the frame studs.
If at first you don't succeed - cheat!!

JC4LAB

Re: Screaming brake blocks

Postby JC4LAB » 11 May 2009, 5:11pm

Thanks but they are centre pull V brakes...

fatboy
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Re: Screaming brake blocks

Postby fatboy » 12 May 2009, 8:50am

JC4LAB wrote:Thanks but they are centre pull V brakes...


Which are canti brakes! If it is a fairly new Galaxy it'll have Tektro Orynx which have a reputaion for screaching.

Different blocks might help.
"Marriage is a wonderful invention; but then again so is the bicycle puncture repair kit." - Billy Connolly

JC4LAB

Re: Screaming brake blocks

Postby JC4LAB » 12 May 2009, 10:04am

Oops.... thanks for the tips everyone..

RJC
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Re: Screaming brake blocks

Postby RJC » 12 May 2009, 1:53pm

A brake 'booster' which is a horseshoe shaped stiffener plate strapped across the brake mounting points can help if the cheaper options don't get the desired result.
It worked for me with a squeaky rear v-brake.