Rather than retype it, I'll offer
this Sheldon Brown article on cantilever brakes. I don't agree with everything he says...I think he is way off on lever pull...but his advice is pretty good. I have 3 bikes with cantilevers and all of them are set up with fairly short straddle cables...about 45°. I use the free floating straddle cables rather than Shimano's stupid link wire. I also use Paul Moon Units for the hanger. The Moon Unit is wider and makes for a more responsive brake
