Canti brake setup problems

[grey-beard]

Hi,
I'm have a few issues, mainly lack of patience, setting up these no brand old cantilever brakes!
Any top advice form the experts would be appreciated, it's been a while since I've used this type, they are basic, no adjustment other than bending the spring I think!?

I will add more pics later.

 

[grey-beard]

Olden days canti help

I'm setting up some Dia Compe 1980s cantilevers and there's no adjustment on the spring tension to help centre the brakes. What was the Olden Days method to do this, or should I just shuffle the pads in the canti clamps to compensate? NB: Frame & fork only have one canti spring hole so I can't...

www.retrobike.co.uk

Just found this thread, it appears that what I have are early dia compe copies! Cool!?
So just bend the springs to adjust tension?
How do you stop the pads rubbing on the tyre when you release the brake? The arc of the caliper seems to move the pad up as it comes away from the rim, so unless I have it set very close, it rubs on the tyre.
Plus, longer or shorter straddle cable?

 

[RetroDavy]

I've found this page on Sheldon Brown useful: https://www.sheldonbrown.com/canti-trad.html

 

[markoc]

I've found this page on Sheldon Brown useful: https://www.sheldonbrown.com/canti-trad.html

Thanks for the SB link - had a read and finally remembered why I can't set up my V's properly. Crazy the things you forget, versus the things the brain decides to remember...

 

[grey-beard]

I'm going to have another go at them tonight. V brakes are so much easier!

 

[hookooekoo]

How do you stop the pads rubbing on the tyre when you release the brake? The arc of the caliper seems to move the pad up as it comes away from the rim, so unless I have it set very close, it rubs on the tyre.

Unfortunately that might mean that the cantilever bosses are not in an optimum position for that particular design of cantilever brake.

Usually there's some up/down adjustment available on the cantilever brake to allow for that, but your brakes don't appear to have any adjustment.

It looks like a very basic design. I hope you can get it working, but if not then a different fork with cantilever bosses in a slightly different position might work.

 

[grey-beard]

Unfortunately that might mean that the cantilever bosses are not in an optimum position for that particular design of cantilever brake.

Usually there's some up/down adjustment available on the cantilever brake to allow for that, but your brakes don't appear to have any adjustment.

It looks like a very basic design. I hope you can get it working, but if not then a different fork with cantilever bosses in a slightly different position might work.

They do seem very basic, but looking at the link above, they are an almost exact copy of the Dia-Compe 981, there is a slot where the pads attach, so could be moved down. They are a right faff! I will try some different pads, I've seen some low profile ones which may help.
Thanks

 

[grey-beard]

I have just had a thought that the rim maybe the issue? It is quite narrow, and the tyre is quite fat, so that combo would mean that the block has to move at more of an arc?
These are the original brakes that came with the frame so I don't think that is the issue.

 

[RetroDavy]

Rim width definitely makes a difference, as does pad height, as does angle of pad as projecting from cantilever body, which links to length of straddle cable (so longer effective straddle cable length dropping the canti arm ends down a bit).

All fiddly. And I do have some three piece forks similar to yours with a set of cantis that just would not work. Looks like yours will, though, with the right combination of angles.

 

[grey-beard]

I'm pretty sure they Will work, but not tonight. They seem very fickle, one side then the other working. The spring tension obviously isn't right, more patience needed I think.