These types of images are very much 'take what you can get' so there's not a lot of critique one can put forth, however, I will suggest that when shooting subjects like this, resist the tempation to zoom in as close as you can on the action; rather have a bit of space around the subject, that way when you crop, you don't have to lose things like the small bit of his left foot.
I feel that while this is a good action image, it would have been much more powerful if you could have got more of the other rider in as well.
Just my $00.02 worth - your milage may vary.
~John