Old centre pull/cantilver question.

[Cavalol]

Afternoon, all.

I have an old tandem (possibly 1980s) and I can't get the front brake to work properly. The off side arm sits fine and goes back into position when the brake is released, the nearside moves fine if the cables aren't attached, but stays in the 'brakes on' position (i.e rubbing on the rim) when the cable is attached. Ive replaced the main brake cable inner as well as the shorter cable between the arms, centralised the hanger and adjusted the cable tension, but still no joy.

Photos show the last attempt and clearly the main cable is now kinked, and the central short one needs better ends. I have noticed the brake adjusting screw is missing though, so assuming it can be replaced, would that then mean the nearside brake could be set to release when cable attached?

Also, are there whole front brake replacements available still new? I've found sone mountain bike ones but.they would spoil the originality.

Thanks in advance, sorry if they seem daft questions!

 

[Punkawallah]

I largely skipped cantilever brakes. Do have center pull brakes on my Galaxy, but never had that problem. Had it on ‘V’ brakes, where tension screws needed adjusting. My ‘go to’ would be to dismantle, clean, grease and re-assemble before doing anything drastic. Could the cable securing device (word) at the bridge cable be fouling the action?

 

[Cavalol]

I largely skipped cantilever brakes. Do have center pull brakes on my Galaxy, but never had that problem. Had it on ‘V’ brakes, where tension screws needed adjusting. My ‘go to’ would be to dismantle, clean, grease and re-assemble before doing anything drastic. Could the cable securing device (word) at the bridge cable be fouling the action?

Thank you. I got a spared (used) cable securing device, I'll try that first and use a new cable, then disassemble the bakes and clean and grease. I take it more modern brakes would fit ok? As a last resort they'd do, as whether they looked original or not, working ones are surely better!

 

[Big John]

It looks like you've got missing adjuster screws on both calipers. If that's the case you could do with finding a couple. Makes life a little bit easier with cantilever brakes. I have them on two bikes I regularly ride and those screws are a godsend.

 

[T4tomo]

Echo the above, the adjuster screws are vital to balancing the brakes, without them your farked.
Re it staying in the on position, is the tension / return spring in the correct place?

 

[raleighnut]

Double echo those adjuster screws are essential,I'd also clean up and 'copaslip' the pivot bosses.

 

[Cavalol]

It looks like you've got missing adjuster screws on both calipers. If that's the case you could do with finding a couple. Makes life a little bit easier with cantilever brakes. I have them on two bikes I regularly ride and those screws are a godsend.

Thanks. Weirdly, I think there's only one per caliper, but the front is definitely missing. I'll look in the spares department at work, hopefully they'll have one

 

[Cavalol]

Update time:

I found a spare screw, went to fit it but it wouldn't go all the way in. I took the one out of the back (so I could measure it and fin another) and then the back brake also locked over on one side, even when I refitted the screw

To make matters worse, I found the front one DID have a screw in it, it was wound so far in I hadn't seen it. Took it out, slowly refitted it and guess what? Same flipping problem is still there!
Do I need to release the inner cable before trying to set the screw? Thanks in advance.

 

[cyberknight]

I have these brake bridges on my canti bike so i can set the cable pull central and the screws keep that set up
https://www.decathlon.co.uk/p/cantilever-cable-and-hanger/_/R-p-292

 

[Ian H]

A safety point: currently you have nothing under the straddle wire - no mudguard or lamp/reflector bracket. If the brake cable breaks, the straddle wire is likely to catch the tyre and send you rapidly over the bars. The fork crown doesn't seem to be drilled, so you might want to improvise something.

 

[raleighnut]

Thanks. Weirdly, I think there's only one per caliper, but the front is definitely missing. I'll look in the spares department at work, hopefully they'll have one

Yeah you'd get away with one screw to balance the tension against the other side spring

 

[raleighnut]

Update time:

I found a spare screw, went to fit it but it wouldn't go all the way in. I took the one out of the back (so I could measure it and fin another) and then the back brake also locked over on one side, even when I refitted the screw

To make matters worse, I found the front one DID have a screw in it, it was wound so far in I hadn't seen it. Took it out, slowly refitted it and guess what? Same flipping problem is still there!
Do I need to release the inner cable before trying to set the screw? Thanks in advance.

Have you removed the arms and cleaned up the pivot bosses, pretty essential IMHO

 

[fossyant]

I have these brake bridges on my canti bike so i can set the cable pull central and the screws keep that set up
https://www.decathlon.co.uk/p/cantilever-cable-and-hanger/_/R-p-292

Same hangers on both my canti bikes. Work great.