# Quick and dirty drop bolt.



## onespeedbiker (May 28, 2007)

My old Italian bike has a rear brake arch about 5mm too high for a standard brake (measures about 55mm). It's not really a big deal because I have some vintage longer reach brakes that work, but it bothered me that I couldn't mount a modern dual pivot Campy brake. The primary problem with this drop bolt is it really can't drop very far or it will contact the tire; also it has to be made with a Dremel tool and a cordless drill. As I was walking through the hardware store looking for inspiration, I hatched the plan to use the alloy sleeves used to crimp stainless cable. 

The pictures show what I came up with. It's a very crude prototype but it mounted with about 3/16" clearance from the top of thr tire and the brakes held on a couple of passes. I will probably remake it with no overcuts and slightly longer to increase the amount of metal holding it together..I still have serious reservations about the strength however.


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## raymonda (Jan 31, 2007)

I would be surprised if that could handle the torque applied during braking.


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## onespeedbiker (May 28, 2007)

raymonda said:


> I would be surprised if that could handle the torque applied during braking.


The only caveat is it is for the rear brake which takes much less torque that the front, but I agree it doesn't look promising using aluminum. Stainless on the other hand might work, but I will need a drill press, which one of my friends just so happens to have,,


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## Kuma601 (Jan 22, 2004)

Those ferrules are pretty strong for the given cable crimping. 3 series stainless steel, 7075 aluminum and 6061 is probably up to this task.


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## abarth (Aug 12, 2008)

The weld is what concerns me. I wouldn't ride that, but it is not my life, so have fun and keep an eye on it.


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## onespeedbiker (May 28, 2007)

abarth said:


> The weld is what concerns me. I wouldn't ride that, but it is not my life, so have fun and keep an eye on it.


It's not welded..


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## abarth (Aug 12, 2008)

Sorry my bad, didn't read your post throughly.


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## paredown (Oct 18, 2006)

U R a genius! 

Since the crimp is one-piece, I would think it would be more than adequate--in theory with the brakes set up correctly, the torque is minimal and the force is on the blocks, pushing back against the crimp & body--maybe some vertical as the brakes grab, but that force should be captured by the bolt through the frame.


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## onespeedbiker (May 28, 2007)

paredown said:


> U R a genius!
> 
> Since the crimp is one-piece, I would think it would be more than adequate--in theory with the brakes set up correctly, the torque is minimal and the force is on the blocks, pushing back against the crimp & body--maybe some vertical as the brakes grab, but that force should be captured by the bolt through the frame.


I don't know if your complementing me or just want to give me enough confidence to use it and see me crash and burn if it fails 

However, I do have enough confidence in the idea to make a more robust version. So here is the QADDB ver 2 (on the left with ver 1 on the right).


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## cmg (Oct 27, 2004)

when it snaps off you can buy a set or a single long reach brake from Harris cyclery. will look much cleaner than the prayer you've put on.


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## onespeedbiker (May 28, 2007)

cmg said:


> when it snaps off you can buy a set or a single long reach brake from Harris cyclery. will look much cleaner than the prayer you've put on.


It was really more of an experiment than a need. I have a couple of brakes calipers that are long enough, I just wanted to see if I could come up with something. On my first real ride, the device worked like a charm, it didn't flex or move out of the original position. But the ride was so rough, lots of tree parts everywhere after the big wind, that I knocked the rear wheel a little out of verticle and there was so little clearance (about 3-4mm) that it was rubbing the bottom of the brake (the rubbing was so minor you would never notice it, but I knew it was there). So I'm going to put the very nice Suntour brake I used before back on. 

What I was really looking for was a dropbolt for a double pivot brake. There are very nice Campy old OEM dropbolts for single pivots, but they are quite pricey these days.


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