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5,234 Posts
I suffered with these things for three years. I distrust throwing parts at my bike, and everybody says that nobody's brakes work during a 'cross race. So I figured my brakes were not really sucking more than anybody else's. I got some Kool Stop pads and sucked it up.
But I got suspicious. They sucked on the road, and correctly set up cantilevers are supposed to be competitive with dual-pivot brakes. I tried lowering the straddle cable. Didn't help. Up high, it was bad. Finally, I busted out my mad engineering skillz and drew some free body diagrams, and decided that they were an intrinsically sucky brake because they had the layout of a high-profile brake but short arms.
I got some cheap Mini-Vs. (Tektro BX3V) Installed them yesterday, nice long ride today including some dirt and mud, favorably impressed.
Back on topic - I notice that the BX3V is a pretty tidy unit. The spring, spring tension adjustment screw, and a bushing are all part of the arm and it would take some doing to take it apart. I notice that the BX3V has bushings.
The Kore Sport cantilever brake is not a tidy unit. Remove the mounting screw and everything comes apart. And it doesn't have a bushing, per se - just a metal sleeve that rotates around the cantilever post itself. I can't imagine that stays exactly clean or low-friction when there's mud all over the place. I also wonder if it twists around on the post and binds.
So how do these things suck? Let me count the ways.
-Stupid geometry makes it impossible to get a level of mechanical advantage similar to other cantilever brakes.
-Badly integrated design. Lots of opportunity for play.
-Uses cantilever post as a friction surface. No attempt to seal dirt out.
For anyone considering Mini-Vs, do it. The BX3V has an 85mm arm, and has pretty slim clearance relative to the rim and takes very little force to operate. I wonder if for old-school short-pull levers (Mine are Tiagra 4500) an 80mm brake like the 926AL might be a better match. But these are definitely "good enough." It's just a more mountain bikey lever feel - I don't bottom them out or anything, and I didn't have trouble modulating on trails just now.
But I got suspicious. They sucked on the road, and correctly set up cantilevers are supposed to be competitive with dual-pivot brakes. I tried lowering the straddle cable. Didn't help. Up high, it was bad. Finally, I busted out my mad engineering skillz and drew some free body diagrams, and decided that they were an intrinsically sucky brake because they had the layout of a high-profile brake but short arms.
I got some cheap Mini-Vs. (Tektro BX3V) Installed them yesterday, nice long ride today including some dirt and mud, favorably impressed.
Back on topic - I notice that the BX3V is a pretty tidy unit. The spring, spring tension adjustment screw, and a bushing are all part of the arm and it would take some doing to take it apart. I notice that the BX3V has bushings.
The Kore Sport cantilever brake is not a tidy unit. Remove the mounting screw and everything comes apart. And it doesn't have a bushing, per se - just a metal sleeve that rotates around the cantilever post itself. I can't imagine that stays exactly clean or low-friction when there's mud all over the place. I also wonder if it twists around on the post and binds.
So how do these things suck? Let me count the ways.
-Stupid geometry makes it impossible to get a level of mechanical advantage similar to other cantilever brakes.
-Badly integrated design. Lots of opportunity for play.
-Uses cantilever post as a friction surface. No attempt to seal dirt out.
For anyone considering Mini-Vs, do it. The BX3V has an 85mm arm, and has pretty slim clearance relative to the rim and takes very little force to operate. I wonder if for old-school short-pull levers (Mine are Tiagra 4500) an 80mm brake like the 926AL might be a better match. But these are definitely "good enough." It's just a more mountain bikey lever feel - I don't bottom them out or anything, and I didn't have trouble modulating on trails just now.