Brompton Rear brake exploded diagram.

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Kell

Veteran
Does anyone have a link to a exploded diagram of the rear brake assembly?

I found this site https://brompton.zendesk.com/hc/en-us/articles/203295871-Download-all-data-schematics But it doesn't include what I want.

The problem I'm having is that the rear caliper appears to have lost its 'springyness'

It's not opening properly meaning there's about 1.5-2cm of travel in the brake lever before it actually pulls the brake.

It also means it's constantly on at the moment.

I'm going to give the whole gear train a going over tomorrow, and thought I'd take the brake caliper of, remove and regrease everything, but wanted to make sure it all goes back together properly.
 

Welsh wheels

Lycra king
Location
South Wales
I read the thread title and thought you were going to say that your rear brake blew up!
 

stephenjubb

Über Member
I've had this, on a brompton, rear brake never has been good, adjusted pads, cables. Then finally traced it to the spring in the brake. Greased it and all good again. Did it on friday as finally got fed up of it catching on the rear wheel.

Alas it went again, could not find a replacement spring so had to buy a new brake, now all great.

If you can take the brake off, or without the readr wheel in, squeeze the brakes alarms together ( without the cable attached ) and see if it has any power. If not then it is the spring and possibly the cause of what you describe.

The rear brakes are not cheap at £30 but it looks like you are doing what I did and exploring all options first, which is good.
 
OP
OP
Kell

Kell

Veteran
I took it all apart, cleaned everything, greased the little ferule on the spring, swapped pads and refitted everything.

I think it's because it doesn't work like other brakes and last time I checked it over, I must have overtightened the nut on the front.

It's only really by taking it apart that I worked out how it works.
 

Phodges

New Member
I have a similar issue and am trying to find a diagram to assemble/disassemble the rear brakes. All I can find is the tech sheets on Brompton and they don’t have rear brakes
 

12boy

Guru
Location
Casper WY USA
I too, have had some issues with the rear brake insofar as the brake lever would not return fully to the non-braking position. I greased the cable, took the rear brake apart, cleaned and greased everything and although it sprang back just fine without the cable attached, with the cable it would not. Tried some v-brake levers that had a lever spring and the lever sprang back just fine, but the leverage provided or lack thereof, wouldn't provide much stopping power, especially on the front. So I went to my LBS and they provided the solution...Jagwire now has "pro" cable housing that doesn't bind the cable. This housing is "non-compression" in that it has straight wire as used on derailleur cable housing and spiral bands as does conventional brake housing so as to not compress under load and still bend well. The cable housing is teflon lined and I was told not to oil or grease the cable as this could cause binding. Here in the US the little caps that go over the ends of the cable housing are called ferrules and although ones big enough to go on the cable housing where it enters the brake will go into the brake arm fine, they will not go into the screwout housing on the lever itself. Jagwire now has a ferrule that fits the cable housing but goes to a smaller diameter on the lever end that will bottom out properly in screwout housing. I have the old style plastic housing levers and perhaps the 2013 and later ones contain a spring or will admit a regular ferrule, but this setup works very well for the plastic ones I have. I don't have any Jagwire stock, but thought I would pass this on to save someone else my frustration with rhe brake lever return.
 
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