Played through the whole game on Linux, no issues. Nothing to say that others haven't said yet, but here goes:
There are too many keys that don't really serve a gameplay purpose. Attacks could be removed entirely, and although I get that you wanted to leave it up to the player whether or not to interact with objects, right now there's no reason to not use them. Perhaps if the levels were more puzzle-like or there was another reason to take a slower path, then it would make sense, but right now it's just a timing check whether the player presses the button at the right moment.
The maximum speed doesn't feel satisfying right now, you reach it pretty much instantly but it's still slow. You could increase the limit but slow down the acceleration to let the players actually build up speed.
You should probably add a small delay between object activations, I could mash the interact key to hit a spring twice which resulted in a higher jump than usual.
I really don't like having to let go of a direction and pressing it again to start turning in the air after a jump. You could add a small delay when becoming airborne, after which the bike starts rotating like usual even if you keep holding down the key instead.
Besides all this nitpicking it was a really nice game though. Now you just need a lot more levels.