Bike in Motion

[shootme]

Some of you know I've been trying to improve my motion (panning) photography, last one I showed was a broom from memory? Anyway, I promised I'd come back when I have something better. I like these couple of shots, would you agree I'm getting closer? I could probably do a better job with composition and contrast, particularly for the 3rd shot. Is there enough motion? What would be your advice for me to get an even better shot. I don't use a tripod, I find it prohibitive. I've also been conscious of the background I'm using for these as well. They were taken mid afternoon.