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Old 01-17-10, 11:02 AM
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meanwhile
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Originally Posted by Metaluna
From what I've read, in addition to feel, the other big benefit of wide profiles is supposed to be mud clearance for CX. They allow you to set the pads far away from the rim but still have enough cable pull to cover the distance while retaining good modulation and adequate stopping power. I too have experimented with wide profile brakes and could never get the supposed massive power out of them that everyone raved about..at least not without setting the pads so close to the rim that rubbing was a problem.
It's not the other benefit, it's the ONLY benefit! From Sheldon Brown:

Wide profile cantilevers have a cantilever angle much greater than 90 degrees. The best example of this type is the old Mafac cantilevers, in which the anchor arm actually sloped downward from the boss in some installations. This design is now pretty much obsolete. Wide profile cantilevers have rather low mechanical advantage, and work well only with levers with a high mechanical advantage.
The 720 isn't quite as extreme as the MAFAC, but they are at least semi-wide angle. They're designed for maximum mud clearance for cross. They're a good design for the intended purpose, but will give acceptable mechanical advantage if tuned properly, but they are NOT designed to Stopping Monsters. In fact, arm length isn't really a guide to canti stopping power, although it looks as if it should be. This is because the distances that determines leverage are the pivot-cable distance - PC on the diagram below -and pivot-show, PS. You need to take their[ b]ratio[/b] - and then factor by the effect of the straddle angle....


Last edited by meanwhile; 01-17-10 at 11:13 AM.
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