I bought an old, but really nice, Nishiki Cresta GT touring frame off of ebay. Frame has all the normal fittings of a full blown touring set, including cantilever brake bosses.
The problem is that I have tried three cantilever brakes on this thing to try and get the pads to line up well on the rim. Brand new Avid Shorty 4's are much to long and the pads end up very high up and can only intersect the tire. I also tried a crummy pair of shimano alivio's that I found, they didn't work either. Then I tried a set of cantis off of my friends NOS Lotus Odessy. The didn't have a model name, but they allowed for more pivot in the pads and I was able to get the pads to line up on the rim by pulling the canti arm outward and pivoting the pad at a more extreme angle to aim at the rim. However, the springs were far too limited in their adjustment and couldn't keep the pads away from the rim.
I currently have a Mavic open pro rim on the rear, and the vertical distance from the center of the rear bosses to the mid-point on the rim's braking surface is only about 17mm. The bosses of course are below the rim, not above.
So I'm wondering if anyone has any good suggestions on how to overcome this problem. Does anyone know of a brake-set where the pads can be adjusted very close to the boss bolt and still have correct spring tension? I do have the option of re-brazing the bosses. I know an extremely competent person for this job, however, I would prefer not to mess with the frame in that way.
another possibility is to create a makeshift Drop-bolt setup and follow Sheldon's example. However I can only really see that being effective for the rear and much more difficult to come up with an affective fabrication for the front.
So there it is! Havachu! no idea if that is how I should spell that but you get my drift.