UKC

My bike suffers from a very squeaky front brake (v brakes). They are so loud most people in my office know when I have arrived at the bike sheds over the way. I don't need a bell because my front brakes are much more effective. But they are really really really annoying. Is there anything I can do to rid them of this bloomin squeak?

PS - please don't suggest I angle the brake blocks forward. I now have wedge shaped blocks and it doesn't work. Do I need to replace the whole thing?

In reply to ByEek:

Put some WD40 on the blocks and the rims, will work wonders.

On second thoughts, maybe better not....

CB

In reply to ByEek:

Perhaps there is a build up of stuff on your rims? Maybe have at them with some degreaser and a scrubbing pad. Could be you need to use some fine wire wool on them too, assuming they are metal rims.

Another thing to look at might be play in the brake calipers themselves. If they are the vibrating element then messing with the pads might not help. Strip, regrease moving parts, rebuild and tighten all bolts up.

Pad/rim combo, some pads might be squeakier than others.

Best of luck

In reply to thedatastream:

Some good tips there. I don't think it is the rims because I have recently bought new wheels and there is no difference in squeakiness. That said, there is a bit of play in the callipers. Even with the bolts tightened right up. Is it worth getting some washers or something?

In reply to ByEek:


Which way have you angled them? The end of the brake block closest to the front of the bike should touch the rim first, placing a thin piece of card between the rim and the rear edge of the block before tightening is one way to get a slight toe in. Are either of the blocks diving under the rim slightly, or rubbing against the tyre?

In reply to EddInaBox:
Great tip for setting the blocks. However, alas no. Last year I had it professionally serviced (squeaky brakes). I recently replaced the blocks and set the front edge against the rim after faffing for hours because to get that slight angle (I didn't know that excellent trick). They were slightly less squeaky until the front of the block wore flat and now they are ear splittingly loud again.

In reply to ByEek:

What brakes are they - older Shimano XTs? They were renowned for squealing.
As others have said, it is probably a minute amount of play in the setup. You could just get some new V-brakes - pretty cheap.
N

In reply to ByEek:

Sounds like it might be the callipers like you say. If, when you apply braking pressure to the rim, the pad can jump on and off the rim, using the give in the arm pivots as that little space to jump in and out of, then this might be the source of your squeak. Problem with this is that if there is no play at all then your brakes wont open and close smoothly and will stick - you want play in some parts, and precision snugness in others.

Normally there is play in one of two places -
1. Play in the arm itself. This is when there is play between the break arm itself and the pivoting deep metal ring fitted within the arm that slips over the fork bosses. This is solved by stripping down the arm completely, servicing it and refitting it. If it doesn't work, replace the whole brake.
2. Between the 'pivoting deep metal ring' and the fork boss itself. This is probably a little harder to suss out. make sure that the inner ring and the boss are both completely clean and that the pivot bolt is greased and fully fitted within the boss. It should be sitting snuggly on top of the deep metal ring, pushing it against the small metal plate at the base of the boss with the three spring holes in it . an additional washer could solve things, but it all depends on the original build quality of both the forks and the callipers.

Depending on you available budget, I'd take it to the local bike shop and ask them to fix the noise. New callipers should be stomachable, but if they suggest new forks, stick with the squeak!

In reply to ogreville:


I think that must be it. New callipers it is. Cheers all!

In reply to ByEek:

Ensure the pads are not siting on the top edge of the rim but sitting with pressure more towards the tire as with some rims have some flex with pressure.

In reply to cb294:



Not as daft as it sounds. WD40 is a terrible lubricant but a very useful degreaser - for example, getting rid of a build-up of brake dust and debris on braking surfaces which could be causing the noise, as someone has suggested. Clean everything thoroughly with good degreaser, then wipe clean with a clean cloth.

OTOH, don't do what I did to my town bike some time last year and absent-mindedly use GT85 for the same job. I ended up running into the back of a taxi next time I was out in the wet.

In reply to ByEek:

Try stealth rubber?

In reply to stewieatb:

Didn´t think of this, but for degreasing I would rather use isopropanol, or any other solvent that evaporates rather than leaving residues after you wipe it off.

CB

In reply to stewieatb:


Thanks for providing a brilliant excuse for buying an N+1 bike. Now I just need to find something to run into