Monday, March 03, 2008


As much as a retro grouch like myself likes to grumble about how nothing was wrong with that old stuff that's now considered obsolete, I must admit that sometimes new stuff is better than old stuff. Brakes, for instance. I usually identify myself as a mountain biker. I have become accustomed to the stopping power of my mountain bike, with its "old skool" hydraulic rim brakes. The suckers just clamp down. If conditions are bad enough to degrade braking, conditions are likely bad enough under the tires that less clamp-down is probably a good idea anyway.

So I've been zipping around on this old road bike and noticing that its single pivot calipers don't really haul my ample mass down from high speeds the way I'd like. Rather than running right out to buy a new set of dual pivot calipers and matching levers, which would cost roughly four times what the bicycle cost me, I planned to try some parts from the old junk box. I have no idea where I scrounged these nifty center-pull clampers, but they've shown me that maybe some new equipment might be warranted. Why? How were they? Sponge-O-Licious! This is probably no surprise to seasoned roadies, but the performance of these brakes prompted me to switch back to the original front caliper immediately. Stopping distances went from mediocre to dangerous.

In the first half inch or so of lever travel, they felt normal. They really felt like they would dig in and slow the bike down well. Then something else happened as more tension was applied. The stopping power leveled off as the lever was squeezed all the way to the bar. Not a situation I'd like during a panic stop. Upon close inspection, it was clear that for that first half inch of lever travel the pads were indeed tightening. Then after reaching a certain threshold. The caliper started flexing, and the pivots could be seen visibly spreading. That's all this caliper has to give.

Thinking a little more about this brake, I could probably improve its performance. If I disassembled the rear caliper and replaced the pivot bolts with longer bolts, adding the cross piece from the rear caliper to the front of the front caliper with pivot bolts first going through one cross piece scavenged from the rear, then through the cantillever arms, then through the other cross piece (similar to the "brake boosters" once available for mountain bike brakes) I could likely reduce the amount of flex significantly. Is it worth it. Hmm. Maybe not this time. My local bike shop will be pleased.


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