I've got some Shimano BR550 cantis on my Bruce Gordon BLT. The front brake has been nearly impossible to properly adjust since I bought the bike last year.
I can either have the brake pads at the proper position OR have the lever nice and tight, but not both at the same time. When the brake pads are in their proper position, the lever and brake cable are very loose and wiggle around freely, and I really have to jam the lever until it hits the handlebars to brake. When I tighten up the barrel adjuster to get rid of the extra slack in the cable, the brake pads are tightly gripping the rim.
The rear brake works fine. I have tried cutting some of the cable housing, tried adjusting the spring tension in the brakes, etc. but nothing seems to work. I'm beginning to think that the springs in the brakes aren't pushing out far enough; the springs stop pushing out when the pads are only 1cm or less from the rim. In the back the springs push out about twice a far as in the front brakes.
Another thing to note is that I took the bike in to a very respectable local shop for a complete overhaul after I rode the thing across the country over the summer, and they did a great job of fixing it up but the brake problem was still there when they were done.
Anybody know what I can do to fix this problem?
[EDIT] I just took apart the front brakes and noticed three little holes on the braze-ons with a little pin on the brake calipers that determines the 'effectiveness' of the springs. I tried moving the pin up one hole, but now it seems the springs are almost too tight and I'm afraid after a while the springs will snap if I leave the brake in this configuration. However, this is the most usable position so far for the brakes.