Two weeks ago I was biking home from campus and the chain on my bike slipped. Then it happened again the next day. In the subsequent days it became a more and more frequent problem. Finally the 4th and 5th gears on my right shifter became worthless. So I lost gears 4, 5, 8, 10, 12, and 15. I thought the derailleur needed to be adjusted.
Today I decided to fix the problem. Contrary to my initial suspicion, the derailleur was innocent. The malfunctioning part was located next door. It was the rear round spiked thing. It caused me a considerable deal of consternation to realize I had no idea what the part was called. I’ve ridden bikes for years and never once considered this.
Oh round spikedy thing, what shall I call thee?
The trouble with the round spiked thing was that it was starting to look like a hockey player. An appalling number of teeth were missing. This explains the chain slippage.
The problem: Missing teeth.
Armed with a diagnosis I set about trying to figure out what part I needed. After some internet searching, and consulting my bicycle owner’s manual, I figured out the correct term. The rear spiked round thing on a bike is called either a freewheel or cassette (or less commonly a rear sprocket or rear chainwheel).
—Begin Edit 8/20/09—
A freewheel and a cassette are not the same thing. They are two very different systems and they are NOT interchangeable. I learned this the hard way. Arrrggghhhh.
—End Edit 8/20/09—
Tomorrow I intend to check a few prices and either pick one up or order one. My online research indicates they can be found for around $20.
I wonder if freewheels have a toothfairy?
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