Author Topic: CSS rim squealing  (Read 4251 times)

martinf

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Re: CSS rim squealing
« Reply #15 on: January 28, 2022, 03:17:23 pm »
If I still have the squealing then it's definitely the brakes. Correct? Not the pads/rims.

IMO, not necessarily. But changing the brake mechanism might work.

Before buying a new brake mechanism, if this is possible and not too hard, it might be worth swapping your brakes front to back to see if that changes things.

Or swapping just the brake pads.

I have (or have had) squealing brakes on my bikes lots of times. Often I only bother to try and do anything about when my wife complains, as she really doesn't like the noise.

Sometimes squealing goes away with time. Or wet weather.

Sometimes it comes back after a period of quiet, usually if I haven't used the bike concerned very much.

Sometimes cleaning the rims stops it.

Sometimes "refreshing" the surface of the brake pads by filing, sanding or grinding works.

Sometimes toeing in the front of the pads works (others report getting the pads parallel, or doing the opposite and toeing them out).

Sometimes changing the make or model of brake pad works. Aztec pads squealed on one of my bikes, so I put Koolstop Salmon on and no squeal. And I then used the same Aztec pads on another bike, where for some obscure reason they didn't squeal.

Sometimes changing the brake mechanism works. I noticed this when I replaced some very worn Mafac cantilevers (more than 32,000 kms and I could feel some play at the pivot) with more modern Shimano ones about 20-30 years ago. The Shimano's are now at about 34,500 kms and still not squealing. 

Matt2matt2002

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Re: CSS rim squealing
« Reply #16 on: January 28, 2022, 04:59:32 pm »
Thanks Martin. Good thoughts.
It appears it's an elimination process.

Working my way through the cheap and quick options.

Since I have new pads to put on, I'll do that tomorrow.

If no cure, I'll pop the rear blue ones on the front.

Stay tuned...

And thanks again to all.

Matt
Never drink and drive. You may hit a bump  and spill your drink

PH

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Re: CSS rim squealing
« Reply #17 on: January 29, 2022, 11:30:04 am »
While searching the forum for something else, I found this which I wrote in 2007
Quote
2007 I've recently put a Rigida Grizzley Carbide rim on the front of my Raven.  If it lasts twice as long as a Mavic I would have broken even.  If it lasts three or four times as long, as some people are claiming it will, it'll be a great saving.  Apart from the price, I'm very happy with it, the wet weather braking is better than with any other rim braking I've had, including Magura HS. The only downside is it squeals, like nothing else.
Oh well, that's memory for you, I have no recollection of that, or if I cured it, I blame it on my ageing... :-[

martinf makes a good point about brake arm length, I didn't have that issue on mine with several brakes, though I didn't max out the tyre size.  It did remind me that the brake and any fork crown light fitting have to work together, something I did have issues with.  Also had the same issue on the Mercury, solved by having a bracket under the straddle wire, which offers loads of clearance, it might possibly have also worked on the Raven if I'd thought to try it.   

Matt2matt2002

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Re: CSS rim squealing
« Reply #18 on: January 29, 2022, 11:33:04 am »
Decided to fit new pads to front squealing brakes.
Tough to remove and replace but got there in the end.

However the new pins don't push down completely.
They are in the correct location, since I can see light through the hole.
It's the end part that doesn't push down due to the tip being curved/looped.
Does it show in the attached pictures?
Should I pinch it together?

Old ones removed pushed down further. There was a small ' loop' I could grab with small nosed pliers.

Best

Matt
Never drink and drive. You may hit a bump  and spill your drink

mickeg

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Re: CSS rim squealing
« Reply #19 on: January 29, 2022, 01:34:45 pm »
However the new pins don't push down completely.
...
Old ones removed pushed down further. There was a small ' loop' I could grab with small nosed pliers.
...

Not sure what the situation is here.  Are you asking if you can use the old pins?  Yes you can.

Are you putting new Salmon pads in instead of pads with a harder rubber?  I previously suggested trying a harder pad.

Matt2matt2002

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Re: CSS rim squealing
« Reply #20 on: January 29, 2022, 05:11:52 pm »
However the new pins don't push down completely.
...
Old ones removed pushed down further. There was a small ' loop' I could grab with small nosed pliers.
...

Not sure what the situation is here.  Are you asking if you can use the old pins?  Yes you can.

Are you putting new Salmon pads in instead of pads with a harder rubber?  I previously suggested trying a harder pad.

I found a pair of unused Salmon pads as I was putting away my tools yesterday, so I thought I'd pop them in rather than try your kind suggestion of a harder pad.
So this morning to popped them in.
Tough to remove and insert but git there in the end.
The new pins go down ok but as my picture shows, the ends stick out. Unable to push them right down despite seeing right through the hole. It's the end ' hook/ tip that doesn't allow the pin to go as far as the old ones did. I know a little tip should protrude but see above picture.

And now no squealing!

I appreciate your advice to buy a harder pad and I certainly would have, if I hadn't found the spare unused Salome ones.

Best
Matt

Ps, I have kept the old pins.
Never drink and drive. You may hit a bump  and spill your drink

martinf

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Re: CSS rim squealing
« Reply #21 on: January 29, 2022, 06:16:15 pm »
The new pins go down ok but as my picture shows, the ends stick out. Unable to push them right down despite seeing right through the hole. It's the end ' hook/ tip that doesn't allow the pin to go as far as the old ones did. I know a little tip should protrude but see above picture.
Ps, I have kept the old pins.

I'd re-use the old pins if they hold the pad securely and are easy to push in/pull out.

I'd have to try again to be certain, but I think that I used pliers to "gently" force down the type of pin shown in your photo, which should lock it in place.

And to remove, I pull fairly hard with pliers. The pin "should" be forced to close and come out easily, but I remember having difficulty removing one pin of that type.

Matt2matt2002

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Re: CSS rim squealing
« Reply #22 on: January 29, 2022, 07:29:59 pm »
Thanks again Martin.

I'll take another run at it tomorrow.

Meanwhile, no squealing has given me a new bike!😉

My stats tell me I had 18+ months on the old ones before replacing them today.
6,000+ miles. Still had at least one third of depth left.
Never drink and drive. You may hit a bump  and spill your drink

mickeg

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Re: CSS rim squealing
« Reply #23 on: January 29, 2022, 09:06:59 pm »
Great that the squealing is gone.  Not sure why that would occur if the only change was replacing with new of the same type, but it worked so why question it.

Matt2matt2002

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Re: CSS rim squealing
« Reply #24 on: January 30, 2022, 10:03:47 am »
Great that the squealing is gone.  Not sure why that would occur if the only change was replacing with new of the same type, but it worked so why question it.

Yes, one of life's great mysteries.
Maybe the old ones were harder?

I'll be interested to read my stats in a year or so time.
Never drink and drive. You may hit a bump  and spill your drink

PH

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Re: CSS rim squealing
« Reply #25 on: January 31, 2022, 10:23:52 am »
Glad it's sorted, yes sometimes the cure is a mystery, maybe it just wanted some love and affection  ;)
Did you get the pin in properly? They are sometimes awkward, seeing daylight doesn't always mean there's clear passage, I sometimes run a drill through them, also turn them over and push the brake onto the pin, you can see then if it's lined up.
I used to wonder if the pins were needed, then one morning setting off on a club ride from the meeting point I spotted a pair of brake inserts on the floor. I thought someone had dropped them out of their pocket, but no, they'd come out of someones bike, new inserts, fitted by a bike shop, no sign of the pins, but I suspect they either forgot to put them in or hadn't done so properly.
I don't adjust my brakes on the arms, they're set for middle wear and thread locked on. I take the arms off the frame/fork to change pads, I find it easier than fiddling around on the bike. It's also an opportunity to give them a good clean and smear some grease on the bosses. 

mickeg

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Re: CSS rim squealing
« Reply #26 on: January 31, 2022, 01:57:11 pm »
...
I used to wonder if the pins were needed, ...

The old rod brake bikes (yes, I am that old) did not have pins in their brakes.  And if you rolled backwards with your brakes on, the inserts could slide out, but often only slid most of the way out instead of completely out because with only part of the pad pressing on the rim, there was  often insufficient friction to force it further out.