Squealing Brakes

For discussions about bikes and equipment.
iandusud
Posts: 1577
Joined: 26 Mar 2018, 1:35pm

Squealing Brakes

Post by iandusud »

I recently built a new front dynohub wheel for our tandem, since when the front v-brake squeals badly. I have tried everything I know of. Toe-in, scrupulously cleaning rim and pads, cleaning and regreasing the bushings. Sometimes there's a temporary improvement but not for long. Never had any problem with old wheel. In nearly 60 years of cycling and doing all my own bike maintenance I've never had a squealing brake that I couldn't cure. Does anyone have any thoughts on this?
ANTONISH
Posts: 2967
Joined: 26 Mar 2009, 9:49am

Re: Squealing Brakes

Post by ANTONISH »

Is there some play in the bushes?
I've had a similar thing with the rear cantilever on my touring bike - it needed quite an extreme toe in.
Didn't have a problem with the front.
jo' bo
Posts: 121
Joined: 8 May 2021, 8:21pm

Re: Squealing Brakes

Post by jo' bo »

iandusud wrote: 11 May 2021, 11:35am I recently built a new front dynohub wheel for our tandem, since when the front v-brake squeals badly. I have tried everything I know of. Toe-in, scrupulously cleaning rim and pads, cleaning and regreasing the bushings. Sometimes there's a temporary improvement but not for long. Never had any problem with old wheel. In nearly 60 years of cycling and doing all my own bike maintenance I've never had a squealing brake that I couldn't cure. Does anyone have any thoughts on this?
When problem solving, always go for the cheapest/ least trouble and usually most logical solution first,

That would be ,try some different brake pads in it just swap them front to back and see if the squeal moves with them.
Then swap the brakes over, then if that fails, borrow a wheel from some where and try that.

If non of those do the trick, there is a very good chance you have a poltergeist
Last edited by jo' bo on 11 May 2021, 12:53pm, edited 1 time in total.
NickJP
Posts: 798
Joined: 24 Sep 2018, 7:11pm
Location: Canberra, OZ

Re: Squealing Brakes

Post by NickJP »

jo' bo wrote: 11 May 2021, 12:18pmWhen problem solving, always go for the cheapest/ least trouble and usually most logical solution first,

That would be ,try some different brake pads in it just swap them front to back and see if the squeal moves with them
Ditto. The stock Deore XT V-brakes on my touring bike squealed initially. I got rid of the squeal by swapping the stock pads for salmon Koolstop pads. I kept the Shimano pad holders and just swapped in these inserts in salmon colour: http://www.koolstop.com/english/v_type2.html.

I've also heard good things from other users about the same Koolstop pads in the grey ebike compound, but haven't tried them myself. They're supposed to cope with the higher speeds / greater weight of ebikes, and so might be worthwhile investigating for a tandem.
rjb
Posts: 7200
Joined: 11 Jan 2007, 10:25am
Location: Somerset (originally 60/70's Plymouth)

Re: Squealing Brakes

Post by rjb »

Lots of recent advice here including cleaning your rims with wd-40. :shock:
viewtopic.php?t=145428. :wink:
At the last count:- Peugeot 531 pro, Dawes Discovery Tandem, Dawes Kingpin X3, Raleigh 20 stowaway, 1965 Moulton deluxe, Falcon K2 MTB dropped bar tourer, Rudge Bi frame folder, Longstaff trike conversion on a Giant XTC 840 :D
zenitb
Posts: 832
Joined: 7 Aug 2018, 9:59pm
Contact:

Re: Squealing Brakes

Post by zenitb »

I wouldn't sweat it. My ride to work bike had this and it helped to warn pedestrians I was behind them. The noise has gone now of its own accord :-)
Jdsk
Posts: 24639
Joined: 5 Mar 2019, 5:42pm

Re: Squealing Brakes

Post by Jdsk »

zenitb wrote: 11 May 2021, 2:22pmMy ride to work bike had this and it helped to warn pedestrians I was behind them.
Yes, and you can choose to use it accordingly.

We started the EV15 with a big zigzagging Alpine descent and full touring loads. I liked being able to hear the squeaky brakes on my wife's bike as it told me where she was.

But I'd still try and stop it happening.

Jonathan
Last edited by Jdsk on 11 May 2021, 2:41pm, edited 1 time in total.
KTHSullivan
Posts: 587
Joined: 4 Aug 2017, 1:15pm
Location: Wind Swept Lincolnshire

Re: Squealing Brakes

Post by KTHSullivan »

rjb wrote: 11 May 2021, 1:54pm Lots of recent advice here including cleaning your rims with wd-40. :shock:
viewtopic.php?t=145428. :wink:
:lol: :lol: :lol:
Just remember, when you’re over the hill, you begin to pick up speed. :lol:
jb
Posts: 1782
Joined: 6 Jan 2007, 12:17pm
Location: Clitheroe

Re: Squealing Brakes

Post by jb »

Badly squealing rim brakes can loosen spokes with the highly resonating vibration that goes through the wheel.
Cheers
J Bro
KTHSullivan
Posts: 587
Joined: 4 Aug 2017, 1:15pm
Location: Wind Swept Lincolnshire

Re: Squealing Brakes

Post by KTHSullivan »

iandusud wrote: 11 May 2021, 11:35am I recently built a new front dynohub wheel for our tandem, since when the front v-brake squeals badly. I have tried everything I know of. Toe-in, scrupulously cleaning rim and pads, cleaning and regreasing the bushings. Sometimes there's a temporary improvement but not for long. Never had any problem with old wheel. In nearly 60 years of cycling and doing all my own bike maintenance I've never had a squealing brake that I couldn't cure. Does anyone have any thoughts on this?
Might be too clean. When the MTB gets its yearly optical bollocking inevitably the discs and the pads get degreased to a certain extent. They sound like a howling banshee for a couple of weeks afterwards, after they have accrued some road crud and or GT85 overspray they quieten down no end.
Just remember, when you’re over the hill, you begin to pick up speed. :lol:
iandusud
Posts: 1577
Joined: 26 Mar 2018, 1:35pm

Re: Squealing Brakes

Post by iandusud »

Thanks everyone for all the suggestions. Rims too clean? - No it's the same when filthy. It'll go away after a while once everything beds in - no it hasn't. Different brake pads - I'm on my third different set with no improvement. Wear on the pivots - this I think is the most likely cause. I've just inspected them and there is quite a bit of "wiggle" on the pivots. Not particularly old having done about 3000 miles and I do most of the braking on the rear disc. Tektro RV-6 BTW. However on closer I noted a fair amount of end float on the pivots, so I have carefully filed down the length of the pivots (not the fork bosses) to reduce the end float to a minimum and reassembled. This has in turn greatly reduced the "wiggle". I haven't tested it because despite the weather forecast of light showers it is chucking it down with thunder and lightning thrown in for good measure! It'll get it's next outing on Thursday so I will report back.

Cheers, Ian
iandusud
Posts: 1577
Joined: 26 Mar 2018, 1:35pm

Re: Squealing Brakes

Post by iandusud »

OK, I said I would report back. Huge improvement. Some squealing when braking very hard but not unbearable (unlike before) and nothing under moderate braking. I'm hoping that it will improve as the brake blocks settle in.
Jdsk
Posts: 24639
Joined: 5 Mar 2019, 5:42pm

Re: Squealing Brakes

Post by Jdsk »

Thanks for the update.

Jonathan
iandusud
Posts: 1577
Joined: 26 Mar 2018, 1:35pm

Re: Squealing Brakes

Post by iandusud »

Further update. After a weekend in the Dales the squeal came back. As an experiment I fitted a full sized v-brake (Shimano XT) from my mountain bike to see if it was any better. Much better as in no squeal. Now I know that the cable pull of the Tiagra 4700 brake lever is not correctly matched to the long v-brake but I did have a "travel agent" to hand but thought I'd try without. I find it works great. I appreciate that I probably have it set up with the pads closer to the rim that with the correct lever and that I might need to adjust the cable more frequently but that's hardly a big job in the grand scheme of things. What I do get is better mechanical advantage giving me far superior braking. So I'm going to stick with this set up for the time being and see how it pans out.
ElCani
Posts: 537
Joined: 5 Mar 2015, 11:24am

Re: Squealing Brakes

Post by ElCani »

Excellent!
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