Do all the stock parts clear the tires? No fender rubbing or issues with the chain guard? Do you drag knee on this bike with stock foot pegs? I dragged knee all the time with my FZ6, but even that was a lot more sportbike than this!
You might need to trim the chain guard slightly, but that's it. You can sort of split it in the back and it's not really noticeable at all. I took mine off before checking, but I'd assume it will be necessary. Different models of tires have slightly different profiles, so your mileage may vary. I'm running Kenda Challengers.
The main reason I over-sized the tires was for looks. The front is no longer in the bicycle tire size range and the rear looks more like it belongs on a motorcycle too. The front fender hugs very tight, but I have no rubbing. As I've said, I've never ridden on stock-sized tires, so I cannot say that there is any handling benefit, but it hasn't seemed to hurt it any.
The pegs are aftermarket, but the position is stock, yes. My riding position has me on my toes all the time on the outer edge of the peg. All this weight on that outside edge means I destroy soft or rubber-coated pegs very quickly. A replacement oem style set lasted about 40 miles
I have even snapped a set of cheap "metal" Chinese pegs in half in the middle of a turn! I've recently switched to a universal Emgo peg made of machined aluminum; so far so good!
Knee dragging on this bike is pretty easy. I made some silly video a while ago with me doing it at like 15 or 20 mph in a parking lot. That said, the bike handles extremely well. It will not hold you back in the corners until you're truly an expert; only your own riding ability will.
Excuse the failure wheelies. I am much better now