Originally Posted by
Gonzo Bob
The crank can't be 110BCD because the smallest ring for that is 33 and the middle on your friend's crank is 32.
It could also be a 4-arm crank.
Good call, I had forgotten all about those that. The 94/58 because they just don't show up too often, and I refuse to acknowledge the existence of those 4 arm monstrosities. For my money, it's hard to beat 110/74 as a BCD, it provides you the possibility of a road double, a road compact, a wide range compact (48/22) or a triple. It's also not stupid expensive to buy rings (I'm looking at you TA).
That however is all besides the point, I think a custom cassette is in order.