bmx action

I've got a friend who is a pretty damn good bmx rider, not pro yet, so I've been getting out to the skateparks with him lately, slowly trying to improve myself with this kind of photography.

I finally got my vivitar 285s working, well only one, and got to bring them out there for some off camera lighting. I'm still trying to figure out the best ways to use them for these kinds of shots. any help would be much appreciated.

first 2 are just ambient light:

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i too am a fan of shooting bmx riders at my local skatepark,tips igot from here said u need to get to a better angle where u don't have the roof of that building in the shot,maybe go to the left of the ramp at the bottom of the ramp and shoot up towards the sky,that would give the appearance he's very high,the dark shots u have have to much distractions going on,u want to have the photo force your eye to the rider and not be distracted by other stuff,try some different angles down lower facing up and post em up.

I REALLY like #3...
thinkin' maybe you could crop the bottom a tad? Like take it up just past the shadow on the quarter pipe? Or maybe just above that angled rail in the lower left?
Either way, I love the bottom-lit almost silhouette-like quality. Very nice!

#3, love it.

thanks for the suggestions and praise folks! much appreciated.

Zhey are all nice but number three is by far best.