Originally Posted by
unterhausen
It really doesn't matter what the OLD of the bike is, the chain rings just have to clear the chain stays. The crank arms don't determine this, you have to get the right bb. A bike shop should be able to help you with that.
But in addition to just clearing the chain stays, the middle chain ring of the crank set should ideally line up with the center of the cassette, for smoother shifting overall and to minimize the chain angle in any cross-chaining gear combinations.