I don't understand why you want to use crap headphones that leak sound and can't be used with a helmet.
earbuds are also crap because they let outside noise in.

I'm telling ya, in canal earphones. blocks out some outside noise (you can still hear cars honking, at best blocks out 25db), doesn't interfere with helmet. It's what they use in auto racing to communicate with the pit. (not this exact model)

http://www.amazon.com/Sennheiser-200...3657154&sr=8-1