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Old 08-10-10, 10:50 PM   #1
Cead_tinne
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Vbrakes "to high"

I'm sure this question has been answered, but I can't find it.

I have an old mid-90's Gary Fisher mountian bike that I'm trying to put Avid single digit 7's on the rear. The brakes fit on the bosses fine, but even with the pads adjusted all the way down, the pads still hit the tire. It seems the bosses are too high. Is there an adapter to fix this problem?

I'm not sure, but i think it had cantilever brakes on the bike before.


I appreciate any help!
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Old 08-10-10, 11:46 PM   #2
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Some of the earlier canti's used bosses that were higher than the later style bosses that are compatible with V brakes. It sounds like you may have a set of these. The good news is that there's a number of nice cantilever options out there now that use the new and easier to set V brake pads that would not be hard to retro-fit to your bike if you can't find a V brake with enough pad adjustment range. At least I hope these new cantis are adjustable enough to fit your older frame.

Last edited by BCRider; 08-10-10 at 11:50 PM.
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Old 08-11-10, 10:16 AM   #3
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Dang i was really hoping there was a way to use the V-Brakes and levers I already bought. I guess i could try Cutting the bosses off and brazing them down lower, but I've never really been any good at brazing....
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Old 08-11-10, 10:27 AM   #4
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And since those joints will be holding against the braking forces you are generating this is NOT a good time to be practicing. Nothing like having one of the bosses bust loose when you're in the middle of a hard stop trying to avoid a collision.

How far out are they? Could you just file out a bit of the groove to give you a little more adjustement range or are they a good 1/8 inch or more out of place?
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Old 08-11-10, 10:39 AM   #5
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Originally Posted by BCRider View Post
At least I hope these new cantis are adjustable enough to fit your older frame.
For the sake of one example, I measured the Tektro Oryx and current Deore v-brakes and the adjustment seemed to be the same, so it's hard to tell which new cantilever brakes would work. If Cead_tinne can check a few other makes then he might find some useful ones.

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Originally Posted by Cead_tinne View Post
Dang i was really hoping there was a way to use the V-Brakes and levers I already bought. I guess i could try Cutting the bosses off and brazing them down lower, but I've never really been any good at brazing....
There are these:

http://www.sinz-racing.com/productpages/sbpe-01.html
or
http://www.bombshellparts.com/shop/B...rakeParts.html

I've never tried them. If you do, let us know how they work. You will have to be able to remove the brake posts.
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Old 08-11-10, 11:05 AM   #6
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There are these:

http://www.sinz-racing.com/productpages/sbpe-01.html
or
http://www.bombshellparts.com/shop/B...rakeParts.html

I've never tried them. If you do, let us know how they work. You will have to be able to remove the brake posts.
Hey i think those would work! I'm going to ask a guy at work if he could TIG weld the bosses farther down, if not i'll be ording a set of those.

THanks guys!
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Old 08-11-10, 11:14 AM   #7
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If you need THAT much adjustment then the bike used some other form of brake altogether. I'm pretty sure that those adapters are to allow you to switch between 26 inch mountain bike wheels and 700c wheels.
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Old 08-11-10, 11:53 AM   #8
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If you need THAT much adjustment then the bike used some other form of brake altogether. I'm pretty sure that those adapters are to allow you to switch between 26 inch mountain bike wheels and 700c wheels.
In the first link I posted it says those adapters move the brake posts 16mm. Cead_tinne should measure and see if this is reasonable for his situation. However: he's already bottomed out the pad in the brake's slot. If he moves the brake down 16mm he can still move the pad back up in the brake's usual adjustment range, and probably be close to where he started. To me this seems modest. Perhaps I misunderstand or we visualize the issue differently.

Those adapters are primarily for BMX bikes, but they are for linear-pull brakes nonetheless. They are because of variation in BMX frames and variability of where the axle will be in the track end on the BMX frame. I have read that Shimano's DXR v-brake, otherwise identical to standard Shimano v-brakes, had a longer slot for this very reason, but can't confirm it.

An adapter for a 26" to 700c would, if I did the math right, have to move the posts 31.5mm. The Mavic version of such an adapter, for example, moves the posts in the wrong direction for the current problem, too.

Last edited by scruggle; 08-11-10 at 12:07 PM. Reason: clarity
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Old 08-11-10, 01:09 PM   #9
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Wonder if it was a frame that used U brakes, they are well above the rim though
if so go find a set of U brakes, Ebay Etc.

Pauls Components, use a round shaft on their V brakes and the shoe holder clamps around that,
they are a precision manufacturer so It works well
you can slide the shoes down to match the rim then ..

Paus also making the center pull Racer, in a version that will bolt onto the hole in the fork crown, sawing off the U brake bosses and not replacing them is another approach too.

Or I have a set of drum brake wheels , then I just ignore the frame boss..
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Old 08-11-10, 10:22 PM   #10
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In the first link I posted it says those adapters move the brake posts 16mm.
16mm will be great. The pads don't clear the tire by a hair when at the bottum of the adjustment, and the calipers adjust up and down 16mm. So those couldn't be more perfect. Thanks

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Old 08-11-10, 10:37 PM   #11
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I'm still not sure what kind of brakes came on the bike, but I'm told it's a 1996 Gary Fisher MT. Tam.
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