Touring cantilever question
 

OK,
I'm trying despairingly to finish a re-build of a 1984 Trek 520 that I got on ebay a couple of weeks ago. The bike was in rougher shape than advertised and had extra some problems for my re-build which was focused on commuting and day long rides out in the country with a large saddle bag. After getting the seller to give me a substantial refund (believe it or not!) I set out to convert it to 700c, new bars/stem/brake levers/seat/pedals, etc. I picked up a set of nice NOS 700c Ritchey 36 hole touring wheels and set out on the build.
Now before you say "Of course you are going to have a problem converting 27 inch wheels to 700c because the cantilever brake studs won't fit!" :) The whole project was based on a really cool set of late 80s dia compe mountain bike cantis that are fully adjustable, really really adjustable with plenty of room to move vertically up and down.
Problem: These brakes have internal springs and you tighten the spring with one wrench while you tighten the bolt with another. Three of the four work great but one will not set and I fear that it never will (after a couple of hours trying everything), they also need a lot of cable pull and even the set that works is tough to get adjusted.
Question: Has anyone ever successfully converted a canti bike from 27 inch to 700c? Are there any brakes on the market that will work for this? And last, Does anyone know how to adjust dia compe VC-900s?

thanks

On my touring rig I will have to move the brake bosses. Sheldon Brown has some good information on this subject. Asyou already have the wheels you might try a set of modern single pivot brakes and see if they fit. In 84 there were both 27" and 700c available so maybe you get lucky with the brake bridge placement, and the single pivots will work.

Don