UNLESS things have changed. They do
NOT make a K&N air filter for the M50 yet.....is it an M50 airkit or did the previous owner swap it out for one from a C50?-(those can use a K&N).
What's the story with the PC? Got one or not?
If ya got's neither, got punch the guy in the face for me! and make me feel better.....ok, ok, forget the violence......at least ask for $300 of what you paid him back, if that don't work, well I don't know, spit in his general direction or something!!!
Good luck and welcome aboard!