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PostPosted: Mon Nov 02, 2009 7:25 pm 
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Location: Bristol
A while back I bought a nice pair of NOS campag brakes for my first road bike build...
Image

I got a front and a back brake (obviously) but due to the forks on this bike being threaded, this part does not fit where the back brake goes correctly.

Image

For now I have put the back brake on the front as it were, due to the threaded forks..

Image
where it works just fine...

I basically need another one of these (shorter) parts for the other calliper so it will fit the frame correctly on the back

Image

Now I have tracked down some older campag parts @ Mercian

http://www.mercianblog.com/2009/10/earl ... pares.html

where I think they might have what I need, but the sorry truth is that I don't know what the above part is called :oops: :oops:

I don't want to ring them up and sound like an idiot - so help a brother out here...please 8) What's this part called?


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PostPosted: Mon Nov 02, 2009 8:30 pm 
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What you have in the picture is the brake pivot bolt. However, you don't need to go to the hassle of replacing it.

Older bikes all has the fork crown and stay bridge drilled straight through to accommodate a long bolt like this which was then fastened by a conventional hex nut. Newer frames and forks use recessed allen key nuts which sit inside the frame and so the 'nut' end is always drilled out to a larger diameter then the 'brake' end.

It looks to me as though you have old-style calipers and newer frame and fork. You can simply cut the original bolt down to the correct length and have a new thread cut on what's left. You're LBS will do this for less than the cost of a replacement pivot bolt, including the cost of the recessed allen key not.

Good luck!

Cheers, Gareth.


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PostPosted: Mon Nov 02, 2009 8:59 pm 
Old School Hero
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thanks for the reply garethrl!

both fittings on the fork and frame are "screw in", the longer bolt wouldn't go through them at all.

From your post I take it this means I can take the whole fitment out of the frame with an allen key? I didn't even realise this..

And you're right, the frame/forks are definitely newer than the brakes.


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PostPosted: Mon Nov 02, 2009 9:16 pm 
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Do you mean the pivot bolt is to thick to pass through the hole as it was drilled? That's a bit strange, though I suppose also that the 'newer style bolts' needed to be a bit thinner in the first place to prevent having to drill away too much metal in order to accommodate the recessed allen key nut - particularly for the rear bridge.

As usual for matters mechanical, Sheldon is your source of information and enlightenment:

http://www.sheldonbrown.com/gloss_ra-e.html

about halfway down the page. We are eternally lucky that such a man embraced both old bikes and the internet.

Cheers, Gareth.


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PostPosted: Mon Nov 02, 2009 9:35 pm 
Old School Hero
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garethrl wrote:
Do you mean the pivot bolt is to thick to pass through the hole as it was drilled?.

I'm afraid so. It's screw in, or nothing.

I think this is best illustrated with pictures of both old brakes

Image

front brake on left, back brake on right.

then pictures of the new "back" brake I have vs the old one

Image

as you can see the campag brake's pivot bolt is WAY too long, even though the screw thread is the correct size for the back bridge.


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PostPosted: Mon Nov 02, 2009 9:54 pm 
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Ok, I think I see where we're going. The pivots themselves don't screw directly into the fork crown and stay bridge. On the Campag one that you have pictured, the unthreaded part would sit inside the fork crown with the threaded part protruding out the back. You would then secure the brake in the correct position with a hex nut.

On the newer rear one the threaded portion sits inside the frame - but only because most of it will be covered up by the sleeve portion of the recessed nut. From the second picture the old pivot bolt does indeed look a bit thicker then the newer one. Bear in mind that once you've

a) shortened the Campag bolt to the same length as the new one, and
b) cut a new thread on the stub that the recessed nut can screw onto

then you will effectively have made the 'old' pivot bolt stub the same as the 'new' one - so it will fit.

I don't think that you'll find an original pivot bolt for a brake this old that will fit your frame. On the other hand, you can modify the current one to fit it, and you'll be able to find an original replacement if future if you decide you want to mount these calipers to an old-style frame using hex nuts. I still think your LBS will be your best bet - assuming they have a set of taps of course!

Cheers, Gareth.


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PostPosted: Mon Nov 02, 2009 10:07 pm 
Old School Hero
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garethrl you are my new hero.

I will get up there tomorrow and see what they're saying.

cheers mate 8)


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PostPosted: Mon Nov 02, 2009 10:14 pm 
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Good luck - and don't take no for an answer! I did exactly this about 15 years ago with a pair of Victory calipers that I wanted to fit to a newer frame - the calipers were about 10 years old at the time. I was able to simply fit the 'old rear' onto the fork, but the 'old front' had to be shortened and re-threaded to fit the rear bridge

In fact, now that I think about it, I have a recollection that the unthreaded portion of the front pivot bolt was too fat to push through the rear bridge, but that could be selective memory.

Cheers, Gareth.


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PostPosted: Mon Nov 02, 2009 10:17 pm 
Old School Hero
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garethrl wrote:
I was able to simply fit the 'old rear' onto the fork, but the 'old front' had to be shortened and re-threaded to fit the rear bridge

that's a precise description of the problem I have 8)


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