Sticking side pull brakes

For discussions about bikes and equipment.
robing
Posts: 1266
Joined: 7 Sep 2014, 9:11am

Sticking side pull brakes

Postby robing » 1 Jan 2021, 2:10pm

The rear brake of my Giant road bike is sticking all of a sudden and won't release properly. It was fine last week when I took it out. It's centred properly but the only way I can release it is to manually open the brake pads apart. It doesn't appear to have a jam nut or anything I can loosen, like in this video https://www.youtube.com/watch?v=hcZOZ2WlmyU

I have squirted with some GT85 but made no difference. It's been stored in my garage so been sub zero these last few nights. Could that be why? Have brought indoors to see if that helps.

Jdsk
Posts: 5144
Joined: 5 Mar 2019, 5:42pm

Re: Sticking side pull brakes

Postby Jdsk » 1 Jan 2021, 2:33pm

Does disconnecting the cable make any difference?

Jonathan

Brucey
Posts: 42102
Joined: 4 Jan 2012, 6:25pm

Re: Sticking side pull brakes

Postby Brucey » 1 Jan 2021, 2:46pm

there are two pivots in a typical Dual Pivot (DP) caliper and both need to be free-moving for the brake to work. They are both adjustable (by various means) and they will both seize up if you use the bike on salted roads at this time of year. In addition the return spring needs to be able to slide freely against one of the arms.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

pwa
Posts: 13624
Joined: 2 Oct 2011, 8:55pm

Re: Sticking side pull brakes

Postby pwa » 1 Jan 2021, 2:51pm

When you pull the brake lever, then release it, does the cable go slack? If not, it could be the cable snagging somewhere.

drossall
Posts: 5094
Joined: 5 Jan 2007, 10:01pm
Location: North Hertfordshire

Re: Sticking side pull brakes

Postby drossall » 2 Jan 2021, 12:04am

As others have said, logically it's either corrosion/sticking in the cable (replace cable and housing) or the caliper (lubricate, if necessary stripping it down). Disconnect the cable to find out which.

peetee
Posts: 2756
Joined: 4 May 2010, 10:20pm
Location: Cornwall

Re: Sticking side pull brakes

Postby peetee » 2 Jan 2021, 6:17am

drossall wrote: or the caliper (lubricate, if necessary stripping it down)


Follow a tutorial or instructions. There is a tiny grubscrew which has to be undone if you don’t want to wreck the brake pivot. It is often hidden, clogged with dirt and/or seized.
Winter had arrived in the land of Kernow. Along with it came wet roads and cool winds.
“Oh, my wheels and coupling rods!” Peetee exclaimed.

pwa
Posts: 13624
Joined: 2 Oct 2011, 8:55pm

Re: Sticking side pull brakes

Postby pwa » 2 Jan 2021, 8:04am

I know the problem could be in the brake calliper itself, but the cable is at least as likely to be the culprit.

robing
Posts: 1266
Joined: 7 Sep 2014, 9:11am

Re: Sticking side pull brakes

Postby robing » 2 Jan 2021, 2:51pm

Thanks for the replies. It seems to have rectified itself now. All I did was bring it indoors for a few days and squirt liberally with GT85. The last time I used it I hosed the bike down and cleaned it, let it dry then it went in the garage and that's when the problem started.

Jdsk
Posts: 5144
Joined: 5 Mar 2019, 5:42pm

Re: Sticking side pull brakes

Postby Jdsk » 2 Jan 2021, 2:59pm

I'd probably take this as a warning and give them a good service.

Jonathan

robing
Posts: 1266
Joined: 7 Sep 2014, 9:11am

Re: Sticking side pull brakes

Postby robing » 5 Jan 2021, 7:49am

Jdsk wrote:I'd probably take this as a warning and give them a good service.

Jonathan


Yeah will do as my headset is now sticking too. This all happened after washing the bike down upside down with a hose - not a pressure washer - so wonder if that's linked.

robing
Posts: 1266
Joined: 7 Sep 2014, 9:11am

Re: Sticking side pull brakes

Postby robing » 7 Jan 2021, 7:48am

I took it in to the LBS to get checked. The headset was ok, no movement in it. He said the stiffness was probably where water had got in from when I cleaned it and similarly with the brake seizing. He adjusted it a bit and all is good. Thanks for the replies.

Brucey
Posts: 42102
Joined: 4 Jan 2012, 6:25pm

Re: Sticking side pull brakes

Postby Brucey » 7 Jan 2021, 8:09am

robing wrote:…. He adjusted it a bit and all is good. .


if water has got into bearings and they have become stiff (even temporarily) they will need more than 'a bit of adjustment' . In particular the corrosion (which is surely what has caused any stiffening) may well be ongoing and this will shorten the life of the headset. Wear rates in corrosive conditions can be x10, x100 or x1000 higher than when corrosion is not active.

The best thing you can do if there has been water in a bearing is to clean and regrease it pronto. If the component has a lube port you may be able to do some good by purging with fresh lube, but lube ports are (sadly) not often seen these days.

Most often bearings on bikes come from the factory loaded with poor quality grease (which is soon overwhelmed in conditions that favour corrosion) and not enough of it to boot. Repacking bearings with more, better quality grease is basically mandatory if you want poorly sealed components to last in the wet.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

hamster
Posts: 3714
Joined: 2 Feb 2007, 12:42pm

Re: Sticking side pull brakes

Postby hamster » 7 Jan 2021, 9:22am

robing wrote:Thanks for the replies. It seems to have rectified itself now. All I did was bring it indoors for a few days and squirt liberally with GT85. The last time I used it I hosed the bike down and cleaned it, let it dry then it went in the garage and that's when the problem started.


I suspect it's a water film inside the cable which froze. It happened to me a couple of weeks ago while out mountain biking.

Jamesh
Posts: 1651
Joined: 2 Jan 2017, 5:56pm

Re: Sticking side pull brakes

Postby Jamesh » 7 Jan 2021, 11:10am

I had a sticking brake that was getting tighter and tighter as I rode!!


Why? The lever was slipping down the drop bars and pulling on the cable!

Ops didn't double check the torque from when I attached them initially!!


Cheers James

robing
Posts: 1266
Joined: 7 Sep 2014, 9:11am

Re: Sticking side pull brakes

Postby robing » 7 Jan 2021, 12:32pm

hamster wrote:
robing wrote:Thanks for the replies. It seems to have rectified itself now. All I did was bring it indoors for a few days and squirt liberally with GT85. The last time I used it I hosed the bike down and cleaned it, let it dry then it went in the garage and that's when the problem started.


I suspect it's a water film inside the cable which froze. It happened to me a couple of weeks ago while out mountain biking.


Yes, I think you are right as the bike had been stored in my garage.