Originally Posted by
TurbineBlade
It's called for. The last set of cottered cranks I worked on had each of the problems I listed ('73 Raleigh 3-speed) and was therefore not an exaggeration. You could have avoided filing the pins, but then your cranks would have been like 170 degrees apart. If you grabbed both crank arms you could probably feel the play as well. Then, riding them 5 miles would create either play or would move the position of the crank again.
They suck -- period. They're never worth messing with, and any potential bike that has them should immediately have them removed as a first priority. Other than learning to drive the pins out and remove the cups before trashing the entire unit, I don't even see the value in a mechanic learning to "work on them" -- (which basically means bashing on things with a hammer, maybe using a punch, and using a metal file to do a cheesy job of filing straight.
Has it ever occurred that the problem lay not in the cranks, but in your own ability to work on them properly? The hardest thing about servicing cottered cranks is the unavailability of decent cotters in the right diameters. Visit any bike co-op or metropolitan bike shop where they work on these daily, and you'll find mechanics familiar with them and have none of the problems you had.