Actually, come to think of it, I once had a throttle cable snap on my '74 Saab, as I was gunning it at a left entrance onto the D.C. Beltway. It was a Sunday, no mechanics around, so after several hours in the median (pre-cell-phone days), I had it towed to a bike shop, got the heaviest brake cable and stop I could find, and I was on my way.
Originally Posted by
Tundra_Man
Years ago I had a clutch cable on a motorcycle fail at a stop light. My wife and I wound up walking a few miles that day.
Never had a cable on my bicycle fail, but seeing as they're pretty much the same thing as a clutch cable I imagine it could happen. How often? Hard to say.