am i missing something?
 

My "new" old bike has shimano biopace (1988) - it looks like the crank arms are threaded to take a cap to cover the bb axle. How do I know if the biopace originally came with a cap? If so where would I buy one.

Ginger

Most cranks take a dust cap. This is to protect the threads-- when you want to take the cranks off, the crank puller threads into them. If the threads get damaged, threading in the crank puller can be, well, interesting, and thus so can removing your crank arms. Your shop probably has some lying around; I've some extras I've pulled off older bikes and keep for emergencies, I am imagine your local shop might do likewise.

Oh course - I'm sorry for the laim-0 question. the heading says Vintage - the last time I worked on a bike Carter was still president.

Ginger

Nothing lame about the question. May have belonged in Mechanics, but heck, I'll answer it.

dust caps also protect us against the horrors of dusty crank bolts...