I don't think a lot of R3s have gearbox problems as we only hear of the ones that do have problems, from my experience it was faulty assembly that caused the gearbox to become increasingly noisy and the gear changes "clunky" when we pulled it down for repairs the a spacer washer was installed incorrectly and some of the gears had the edges worn off, the detent spring was bent and the cam chain tensioner almost worn down to the metal, also my water pump seal leaked at 15000Klms a total of 46000 Klms of gentle riding and meticulous servicing ,but I must say a lovely ride while it lasted ,others have more than doubled that mileage or more trouble free