Not at all common, in fact pretty well unheard of. Is it the final drive (the part with the oil in it) or the drive splines, which is the part where the rear wheel connects to the final drive? The splines are known to wear if not properly greased every tyre change and if the final drive is not properly aligned, causing abnormal wear. The rear wheel rubbers and alloy inserts do need replacing when they wear (I did mine at about 140,000kms or so) or else the rear wheel gets excessive wear and may need to be replaced. I have 212,000kms or so on mine.