Just got back from a 6 mile ride. About 5 youths, some on bikes were blocking the path. When I passed them, one asked if he could jump on the back, the other said "oh, I can cycle quicker than that" I said "come on then" and he started pedalling like crazy. I opened the throttle and the acceleration was immense, and he quickly realised he would never catch me up and he stopped. All his mates started laughing at him, and I couldn't stop laughing either!