Bicycle Mechanics - Brake Bridge Question

OK, this may be a stupid question, but is this bridge designed for fenders only, or is it safe to mount a center-pull caliper to it?

The bike has Canti's but no way do they have enough adjustment to allow for 700c wheels, but by mounting a center-pull caliper on the bridge there is plenty of adjustment.

http://img838.imageshack.us/img838/872/dscn0364t.jpg (http://imageshack.us/photo/my-images/838/dscn0364t.jpg/)

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It should work fine for brakes. Roger

It should work fine. Just make sure you have the curved spacers for the brake mounting bolt to avoid crushing the bridge tube.

Also, depending on the hole diameter in the bridge you may need "external nutted" brakes instead of the newer recessed nutted brakes. If the hole is 6 mm on both sides you will need an external nut or you will have to enlarge the seattube side of the hole (and only that side) to 5/16" or 8 mm to accept the recessed nut.

Another alternative if you can only find recessed nut brakes is to use a front brake in the rear as it's center bolt is long enough to accept an external nut.

Also, depending on the hole diameter in the bridge you may need "external nutted" brakes instead of the newer recessed nutted brakes. If the hole is 6 mm on both sides you will need an external nut or you will have to enlarge the seattube side of the hole (and only that side) to 5/16" or 8 mm to accept the recessed nut.

Speaking of which, how'd you get such a nice clear photo from the seat tube side of the brake bridge?

To drill out the brake bridge, I clamp a drill bit with a vice grip and twist it back and forth by hand. It's more easily done than it sounds.

Speaking of which, how'd you get such a nice clear photo from the seat tube side of the brake bridge?

To drill out the brake bridge, I clamp a drill bit with a vice grip and twist it back and forth by hand. It's more easily done than it sounds.

I just placed the camera in (Macro) and pressed the button LOL.... I think I got kucky.

The hole in the bridge is 6mm any suggestions on brake calipers? The rear needs to have about a 64mm reach. I was thinking of 70's Dia-Compe style center-pulls like these?

http://img854.imageshack.us/img854/2774/centerpull.jpg (http://imageshack.us/photo/my-images/854/centerpull.jpg/)

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If you want to keep canti's, maybe you should call VO. Their Grand Cru canti looks like it has a lot of adjustment.
Someone on VO's blog went from 26" mtb wheels to 650b on his surly using those canti's
Tektro CR720 might have enough adjustment also.
Also older Shimano BR MC70
LINK http://www.flickr.com/photos/stronglight/6032423553/

If you want to keep canti's, maybe you should call VO. Their Grand Cru canti looks like it has a lot of adjustment.
Someone on VO's blog went from 26" mtb wheels to 650b on his surly using those canti's
Tektro CR720 might have enough adjustment also.
Also older Shimano BR MC70
LINK http://www.flickr.com/photos/stronglight/6032423553/

I've tried every way possible and nothing will work. I'm not a big fan of Canti's anyhow.

Here's another brake that has the needed reach: http://www.tektro.com/_english/01_products/01_prodetail.php?pid=66&sortname=Road+Bike&sort=2&fid=9

They apparently come in both recessed and nutted versions.

I'd get a better brake to go on the existing bosses, you might find a shorter arm V brake OK

I've got Magura's hydraulic rim brakes on one bike , none better. Kool stop salmon compound pads

Plain post , Eagle Claw for what brake is on there.

I'd get a better brake to go on the existing bosses, you might find a shorter arm V brake OK
Apparently the bosses are located too far from the new 700c rim to make the pad adjustment possible so no boss mounted brake is suitable.

I've tried every way possible and nothing will work. I'm not a big fan of Canti's anyhow.

Thats what makes the world go round.
Tektro has a realllly long reach side pull,http://www.tektro.com/_english/01_products/01_prodetail.php?pid=66&sortname=Road+Bike&sort=2&fid=9
But if you want to use centerpulls as pictured you may might want to look at these extra long reach Dia-compe's http://sheldonbrown.com/harris/brake-calipers.html (http://sheldonbrown.com/harris/brake-calipers.html,(They'll) (they'll probably flex and might be noisy) or you could make some drop bolts ala Sheldon's design if you can't find anyone who still has a few laying around'

added
You might wind up having to cut the canti bosses off if they interfere with the calipers.

Thats what makes the world go round.
Tektro has a realllly long reach side pull,http://www.tektro.com/_english/01_products/01_prodetail.php?pid=66&sortname=Road+Bike&sort=2&fid=9
But if you want to use centerpulls as pictured you may might want to look at these extra long reach Dia-compe's http://sheldonbrown.com/harris/brake-calipers.html (http://sheldonbrown.com/harris/brake-calipers.html,(They'll) (they'll probably flex and might be noisy) or you could make some drop bolts ala Sheldon's design if you can't find anyone who still has a few laying around'

added
You might wind up having to cut the canti bosses off if they interfere with the calipers.

to me, it looks like the cantis hit too high.

Is this a 27" to 700c conversion?

to me, it looks like the cantis hit too high.

Is this a 27" to 700c conversion?

Yes..... Any other ideas?

Yes..... Any other ideas?

What's wrong with the C-pulls you were considering? Properly mounted with the half round spacers they'll do fine.

BTW- if you can't find the right spacers, take a piece of scrap, drill a hole the diameter of the bridge. Drill a 6mm hole at a right angle. Hacksaw it in half and you're good to go.

[QUOTE=FBinNY;13560112]What's wrong with the C-pulls you were considering?[/QUOTE

Nothing, I think that they would work great, but I feel like everyone is talking me out of those. So, I wanted input on somethin I may have been overlooking. Do you think these would do the trick?

[QUOTE=FBinNY;13560112]What's wrong with the C-pulls you were considering?[/QUOTE

Nothing, I think that they would work great, but I feel like everyone is talking me out of those. So, I wanted input on somethin I may have been overlooking. Do you think these would do the trick?

Absolutely, probably far better than a Canti or V-brake with bad geometry.