It is a myth that synthetic oil will prevent proper break-in of an engine.
If it were the case, then why do so many motorcycles AND automobiles come from the OEM with synthetic oil in their crankcases?
The single biggest factor in break-in is to vary speed and gear, being careful not to drone down the interstate at a constant speed for two hours on your way home from the dealership.
I hear this all the time on weekend rides: "Oh, I'll have to hang back, I'm still breaking my bike in." Well, the best way to break a new bike in is a spirited ride through a set of twisty roads, varying speed, throttle, gear, etc. No where in my manual does it say not to exceed a certain RPM or speed. It doesn't even tell me not to redline the engine.
All it says is not to hold it wide open for prolonged periods of time.
Don't abuse the engine, but give it some throttle. Ride it (almost) like you're gonna ride it.
Last edited by yankin&bankin; 11-04-2008 at 09:34 AM.