The only 2 things that really annoy me on my bike are both aftermarket and can be fixed (I've just been lazy)
1) The freakin Ohlins steering damper... I love it, but it rattles and vibrates and drives me INSANE!! Sometimes I just reach down and grab it and hold on to it for awhile just for some quietness, lol. I've tried all kinds of bushings and rubber pieces, nothing I've done will shut it up, lol
2) I love my high mount exhaust, but the midpipe on the right side won't allow me to move my foot back on the peg and totally screws up my body positioning. I really need to get a different one
Really the only complaint I've ever had about the bike itself is the longer throw for the shifter. I've ridden other bikes, particularly the RC-51, where the shifting was super quick and easy, whereas the F4i's are a little more notchy. It's not THAT bad though. Oh and the clutch cable that always runs in front of the speedo, but that can be fixed with a little metal wire (which I did and it works great), so it's not an issue anymore
I still love my bike though