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As part of a bike rebuild I'm working on, I replaced the old cantilever brakes with new Shimano V-brakes.

The problem is that the new front brake doesn't seem to fit with the wheel. The rim walls are relatively low compared to brake pads and the brake pads can't go any lower. In fact where they sit now is also problematic because it's always touching the rim walls.

Attached is a photo of the bike.

Update: It's a 28/700c Villiger frame. I double checked it.

enter image description here

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    Is this a relatively old frame? Could be a 27" wheel that has been fitted with 700c rims ? – Criggie Feb 23 '16 at 23:48
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    The frame is made for 700c rims. So were the original ones. – Daniel Feb 25 '16 at 11:33
  • Sounds like you need to refit the original cantilever brakes or find some V brakes that have more tolerance. I would avoid any sort of Boss adapter to lower the threadded hole, mostly because they're brakes, the one thing you need to work right in a problem. If you're dead keen on keeping the frame and fitting V brakes, consider asking a proper frame builder for a quote to move the bosses down. – Criggie Feb 25 '16 at 13:13
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Your frame is designed for the type of cantilever brake you already had, which has pads closer to the pivot than modern brakes. Unfortunately it looks like you are stuck with your old brakes.

The old brakes can be improved with new cables and pads and lubricating the pivots.

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  • Is it possible to get new cantilever brakes that match this design? for example Shimano BR-CX50 Cantilever? – Daniel Feb 23 '16 at 20:59
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    Cantilever brakes is a design – paparazzo Feb 23 '16 at 23:32
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    The pic looks like it would be spot on for a 27" wheel if it's a 700c now. – whatsisname Feb 24 '16 at 5:16
  • True. The crankset doesn't look that old though, and the OP claims otherwise. – ojs Feb 24 '16 at 19:40
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The first thing is, do you have the right wheel size in this bike?

People often convert 27" bicycles to 700c, which requires 4 mm more adjustment downwards on the brakes (which looks about to what you need, so it wouldn't surprise me if this was the case).

In any case, you need to either:

  • Try a different V-brake. Some will have more adjustment than others. Paul's Moto BMX will probably have the most possible, but is a very expensive V-brake.
  • Try a compatible cantilever brake. I'd try the Tektro CR720 or similar to start (this is a standard modern cantilever brake). Some frames have problems with clearance for this, and the best option is to go to your local bike shop and source an old cantilever brake (or ebay). I've also heard that Planet X's Frog Bollox is good for this application.

Note that V-brakes and cantilever brakes use different brake levers.

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  • Yes the new wheel is the exact same size as the old one(was changed with a dynamo hub) – Daniel Feb 24 '16 at 15:56
  • Yeah, but the old wheel might have been a 700c in a frame designed for 27" to begin with, and the old brakes had enough adjustment to make this work. – Batman Feb 24 '16 at 16:25
  • Possibly. The little research I did about Villiger the producer of the frame reveals they didn't have any frames designed for 27" and the previous owner of the bike claimed he hadn't replaced anything. – Daniel Feb 25 '16 at 11:47
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Had the same problem. The answer is spacers. Each braking pad axle has two spacers one on the outer side (where you tighten the pad) and one of the inner side of the brake arm (towards the wheel). One of them is short and the other longer. You have the long spacer on the inner side (they usually come like this). It should be the other way around. Switch them and place the long on the outside and the short on the inside. Ensure that all other parts (washers eg) remain in the correct place.

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  • How can spacers make the brake pads sit lower? – Daniel R Hicks Jan 30 at 22:28

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