Author Topic: Caliper brake set up  (Read 4794 times)

Matt2matt2002

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Caliper brake set up
« on: August 24, 2022, 08:58:39 PM »
Trying to adjust/ fix my son's front brake.

It's a caliper side pull. Not familiar with this one.

It was juddering so removed nut bolt and washers. No grease here so cleaned and oiled.

Put back together but not sure if washer nut bolt sequence.
Not sure it was set up correctly.

Sheldon Brown does not show an exploded diagram.

On the centre bolt front the front is;
Locking nut cap, nut , 2 washers ( one curved), the 2 arms, washer, spring and the piece the spring sets in.
The bolt passes through the fork and then rusty bolt at rear

Thoughts folks?

Diagram would be nice ! 😉

Matt at 30°
NJ USA
Never drink and drive. You may hit a bump  and spill your drink

Danneaux

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Re: Caliper brake set up
« Reply #1 on: August 24, 2022, 09:27:47 PM »
The setup/assembly as pictured looks about right to me, Matt, complete with the thrust washer at the rear, behind the trailing caliper.

The basic problem with this sort of stamped-steel sidepull is the thin arms in the same plane as braking forces and they aren't very rigid. They clamp "okay" but judder under braking as they really can't resist the forward movement of the pads against the rim very well.

I'd say lube, adjust out any excess play, lock in the adjustment and call it done. Fitting new/uprated brake shoes can actually make braking worse with thin-armed, long-reach stamped sidepulls like these. I know...I've got a set on my 1970 Motobecane Astra U-frame Folder.

Best, Dan.
« Last Edit: August 24, 2022, 09:52:11 PM by Danneaux »

Matt2matt2002

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Re: Caliper brake set up
« Reply #2 on: August 24, 2022, 09:35:50 PM »
Thanks Dan.

Yep, it's a cheap bike with cheap components.
It gets my son to and from work.
He doesn't cycle for pleasure, ( I'm ashamed to admit ! ).
I'll give it a clean and tweak while I'm here.
My duties are looking after the cat and overseeing a new kitchen fitting.
It's been made quite clear to me that the cat comes before the $xxx,xxx kitchen!

Thanks again

Matt at 30° and covered in cat fur.
Never drink and drive. You may hit a bump  and spill your drink

mickeg

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Re: Caliper brake set up
« Reply #3 on: August 24, 2022, 09:55:57 PM »
It can help if the part of the brake shoe that is farthest forward contacts the rim first as you apply the brakes.  Then as you tighten the brakes further, the entire brake pad grips the rim. 

If you have a stiff piece of paper like a business card, I think one or two thicknesses of that type of paper is about the right difference between the two ends of the pad for angle of the pad against the rim.  Not sure if I am being clear here.

Newer brake pads often come with some spherical type washers that make angle adjustment easy, older brakes with thin metal arms like the one cited often were simply bent for this type of adjustment since they lacked such washers.
 

Matt2matt2002

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Re: Caliper brake set up
« Reply #4 on: August 24, 2022, 10:03:49 PM »
Thanks Mick.
Your comments were quite clear and I've tweaked my own brakes in a similar way.
However on my son's bike there is no 'nose in' adjustment.

Maybe the arm could be bent but I'm not sure I'd want to take that risk.

Does the picture show the set up ok?
Never drink and drive. You may hit a bump  and spill your drink

mickeg

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Re: Caliper brake set up
« Reply #5 on: August 25, 2022, 01:07:25 PM »
Photo shows it just fine.

Matt2matt2002

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Re: Caliper brake set up
« Reply #6 on: September 05, 2022, 03:32:27 PM »
Many thanks folks.
After another hair raising ride I bit the bullet and took my son's bike to the local shop.
Only a 5 min walk away and they knew their stuff.
They had a replacement for the front and fitted it in 24 hours.
A 10 day wait for the rear part but that's not so bad and I'll leave that to my son.
$49 parts and labour.

Off for a final ride to Keyport from Matawan.
Fly back home tomorrow.
Sad to leave son and daughter-in-law but looking forward to seeing my wife after 3 weeks away.

My third time in usa and it's growing on me.
I'll be back.

Best

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

jimi84

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Re: Caliper brake set up
« Reply #7 on: April 17, 2023, 08:27:55 AM »
One main thing:
When reassembling the brake, the washer-nut-bolt sequence should go like this:

Locking nut cap
Nut
Curved washer (this goes against the fork)
Caliper arms (one on each side of the wheel)
Washer (this goes against the caliper arm on the outside of the wheel)
Spring
Spring holder (this goes into the caliper arm)
Bolt

Matt2matt2002

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Re: Caliper brake set up
« Reply #8 on: April 17, 2023, 10:26:07 AM »
Thanks Jimi
That's spooky, I was just chatting to my son in Matawan NJ yesterday.
Good advice re nuts/ washers.

I'm back in Aberdeen now but will be over there again in November to welcome my new grandson. And check on the bike!

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