I bought a Sony DSC-V1, its very small which is great for carrying around but makes it hard to hold without obscuring something important with your fingers and means the battery is small, turning the screen off helps recover battery capacity. It has two big plusses for action shots though. One is that it has almost no shutter lag (no more pics of back wheels) the other is that it can be set to continuous focus so forget about holding the shutter halfway down, just pan with the rider and shoot when you want