Walter Mitty said:Fred Roses said:Scott my Centaur FD and crank with 50-40-26 work perfectly (not usre
abiut a 24). The rear is XT 12-32. I use a chain-watcher to manage the
big drop from 40 to 26 teeth.
Chain-watcher?
Dear Mr. Thurber,
Like train-spotters, chain-watchers are mechanical voyeurs.
They attend the Tour and exclaim to each other, "Ugh--PC-48!
Look, Wipperman nickel plated! Oooh, it's a $300 titanium
job with holes in the side plates!" During the off-season,
they furtively haunt chain-saw competitions and--
Oh, you meant to ask about chain-keepers, the
pocket-protectors of the bicycle world.. Sorry.
They're plastic dinguses that mount around the bottom of the
seat tube next to the front sprockets. Looking down at them,
they resemble a comma wrapped around the frame:
_____________ sprocket (imagine a chain)
_______
/ \ chain keeper (imagine a seat tube)
\____/
You rotate them until the tail of the comma almost touches
the top of the smallest chain-ring just under the chain,
leaving no room for the chain to fall off and land on the
bottom bracket--it just hangs on the chain-watcher, high
enough and close enough to the sprocket to be shifted back.
Google for Deda Dog-Fang (dog-fang sounds more ferocious
than comma-tail), and you'll see an example. They protect
paint jobs and are even semi-built-in to some carbon frames,
but the real advantage is that they let you recover a chain
dropped off the front sprocket by fiddling with a gear-shift
instead of stopping to wrestle with an oily chain.
Carl Fogel