Fun game! I can't tell if it was performance issues or a bug with the movement, but it seemed like the guy will slow down and speed up at random (as far as I could tell at least). It seemed like he'd slow to a crawl and then lurch forward, which made it a little frustrating. I think more control over the movement in general, combined with a more interesting set of obstacles would tie this together. Maybe even something where the points you score allow you to upgrade to new inner tubes, with better stats or new abilities like jumping? I think finding a positive feedback loop like that would make the game highly replayable. Great job!