<VV> Fan Belt Physics

[paulsiano at yahoo.com]

I'm asking for a friend who keeps flipping fan belts on his Corvair at higer rpms.  
 
Where does the flip begin?  Is there some sort of standing wave that develops at a particular rpm at a particular physical point?  If the flip always begins at the same place, could an enclosure (guide) prevent the problem?
 
I've had at least one Corvair continously since 1964 but not a Corvair engine for a very long time.  I apologize if I'm asking a question that has an answer that is common knowledge.
 
Any thoughts will be appreciated.
 
Paul Siano