My banshee has never had any rebuild or port work done on it. I bought it about three years ago from a friend of mine who wanted a fourstroke. It always seems to run Great when warmed up. I might do a compression test on it and see if it has lost any. Last I knew it was drawing 115 on one side and 110 on the other, and that was a year ago when I put my coolhead on.Banshees are easier to start than all kickstart quads out there, and I could be sporting a weak motor and not no it. I've been doing alot of thinking on which to do ...you know....porting or rebuild to a big bore...not to drastic.....but reliable and durable.