Sorry to be redundant but would appreciate some reassurance that Mobil 1 15/50 is THE oil to go with for the 4 stroke. I am just about done on my second rebuild and am looking forward to riding on the upcoming long weekend here in Canada. I buy the Mobil 1 at Canadaian Tire, it has the red cap and is an aoutomative oil. Brian at Moto-X here in Laval thinks I'm nuts to run this and mentioned a few experiences where motors that were run on Mobil 1 got quieter after changing to a motorcycle specific. Is there any merit to this or should I stay with the Mobil?