Hi! I also have that free play on the gearbox shaft and about the same amount. First I thought the clutch basket is loose but it's the whole shaft moving. Oh well, so many noise sources on that engine, crankshaft nut on my XT660R was not finger loose, but I still managed to tighten it a fair amount until 120Nm. Haven't started the engine yet, still have to check valve clearances, but hopefully it will make less noise then.