I'm running the standard jetting at about 500 feet above sea level; if I rode it more in the extreme heat right now, I'd probably have to lean it a bit. The motor is bone stock in all respects.
My jetting feels very crisp (in cooler weather) and the plug looks good. I had the same detonation issue you describe. As the previous post said, a 50/50 mix of VP C12 and 93 octane pump gas completely eliminated the detonation and made the throttle response a bit stronger. The motor really rips.
BTW, make sure you keep your exhaust valve cables adjusted properly. Mine was a bit loose after about 10 hours of riding time. If you get some slack in the cable (usually during the break-in period) you'll lose some top end pull.
My jetting feels very crisp (in cooler weather) and the plug looks good. I had the same detonation issue you describe. As the previous post said, a 50/50 mix of VP C12 and 93 octane pump gas completely eliminated the detonation and made the throttle response a bit stronger. The motor really rips.
BTW, make sure you keep your exhaust valve cables adjusted properly. Mine was a bit loose after about 10 hours of riding time. If you get some slack in the cable (usually during the break-in period) you'll lose some top end pull.