Was wondering if anybody else has this problem? I find that because I'm a learner, riding slow, and not as fast as traffic, particularly on wet days, that cars/bikes in my lane behind me, accelerate quickly behind me, then change to right/left lane at last second, and pass me very quickly. This hasn't caused any problems so far, as my head checks tell me they are there so I haven't merged into them. BUT, I don't like being surprised like that, and it feels like they have come out of nowhere. This never happened while in a car, because I could usually see them in my rear-vision. Do many others have this problem? I was thinking of either bar-end mirrors or a riderscan to help. Or is there a technique I'm missing.