On the front I have a kenda 120/80-14 M/C 58S, & the rear I have Pirelli Diablo scooter 150/70-13 M/C 64S. The back wheel it's seems to me slips around when on loose gravel which gives me a bit of a fright, maybe all tyres would have slipped on the same surface, I'm not sure. It just made me wonder whether the tyres I had on were the best for looser surfaces or when road conditions get hazardous. Food for thought. Does anybody else use these tyres? How do you rate them? Or have you had a scare like me on a loose road surface & thought I wonder if there's a better tyre available to save my skin in such a situation?