fred@umcp-cs.UUCP (03/21/84)
Gee. I seem to have started quite a ruckus with my question. Perhaps I should explain my position. For years I've been riding a one-speed bike with coaster brakes. I'm shopping for a good 10 or 12 speed bike in the $200 - $250 range, with which I plan to make the 6 mile round trip from home to campus which I've been using the one-speed for, and get into some longer trips on weekends. I'm a little worried in shopping for a bike that, since I'm unnacustomed to riding a 10-speed, I'll be at a disadvantage in noticing differences between models which may seem great to an experienced rider. Maybe I didn't use the correct terminology in describing the front-freewheel bike. Here goes again: A typical 10-speed has the ratchet mechanism (the gizmo that disengages the drive train when you stop pedaling so the pedals aren't driven around when you coast) on the rear axle (``b'' see figure #1). Thus, when you coast, the chain, front and rear gears, and the pedals are stationary. The front freewheel bike disengages the drive train at the crankarm axle (``a''), so that only the pedals are stationary. The chain, and both sets of gears, continue moving as long as the bike does. ____ ___, __) | \\ /|===========\\ _____// \\ //\\____ - // \\ + // -\\ - / //____---|-\/ / \\ \ | b========(a) | | @ | \ -------|-/ \ / -____ - + -____ - Figure 1 One of my objections to it were that, since the chain is constantly moving, propelled by the momentum of the bike, if something gets caught in the chain it would be drawn in, 'till it jammed, which would lock the rear wheel. It turns out that there's a slip clutch located on the rear axle, so this isn't quite as dangerous as it first seemed. Other dealers have told me that this setup is expensive to have repaired, because of the nonstandard nature of the parts, so few bike shops will have them in stock. One dealer claimed that the gearshift cables were nonstandard, cost $10 apiece to replace, and break about every four months. Fred Blonder harpo!seismo!umcp-cs!fred fred.umcp-cs@CSNet-Relay