I have bought a cr720 to replace the Oryx on the front wheel in the hope that it will improve braking and get rid of shudder. I am reasonably familiar with setting up cantis but their are a few points about the 720s I am not sure of.
Firstly, the instructions don't give any guidance on the height or angle of the straddle wire other than having enough clearance above it to the cable housing. I know that the angle of the straddle wire makes a large difference to ordinary cantis. What should I aim at with these? 90 degrees?
Secondly, a couple of minor queries on the yoke. I suspect this will be obvious when I actually fix it but I am not sure about the main brake cable fixing bolt. Normally in this type of fixing there is one fixed piece of metal (brake, straddle yoke etc) with a bolt, nut and washer. The cable goes through a hole in the bolt and the nut is tightened to trap the cable between the washer and fixed metal part. In the 720 yoke the metal bit is two sides of one molded metal part. Using the normal method to clamp the cable will involve squashing it between the two sides by bending them together. Is this right? I am just a bit concerned about the stress on the yoke.
The other strange aspect of the yoke is the grub screws that hold the straddle cable. One simply pushes against the other side of the yoke. On the other one there is another hole opposite that has a screw in it. I don't understand the point of that screw. Why aren't both sides the same?
Another question is about the pads. I wasn't expecting them to be the best but I have seen a couple of references on line saying that they wear the rims badly. They do seem quite hard, almost plastiky. Are they really that bad?