I think you have a solid foundation for a game here, but it could definitely use a lot of polish. It seems that you over-scoped for the time constraint: consider refining just the racing part, as there's still a lot of good work you can do there.
For instance: I was able to get my bike into a space between lanes where cars didn't spawn -- I didn't have to touch the controls for the rest of the game; I could have gone on that way until my computer died or the power went out. If you introduced some control drift, then the player would have to be more actively driving (and you would have been more in line with the prompt!).
The "unlockables" system becomes broken because the core racing game is easy to cheese -- I got 50,000+ coins by just getting in a sweet spot and doing a wheelie until I got bored and crashed my bike. Then I was able to unlock everything.
Here are some bugs I noticed in the core racing game:
- distance counter doesn't count right
- trying to start a level without actually selecting the level locks the player in a broken loading screen
- clicking on "Watch" does nothing -- I presume this is supposed to serve me an ad?
- initial acceleration with forward doesn't work -- I speed up by using the brake
I'll say again that -- for the jam -- you should have focused on making a tight core-game-loop so far as the motorcycle racing is concerned. Such a game would be really fun, and it's unfortunate that -- as the game stands -- the racing is hampered by a buggy and, frankly, unnecessary menu system.
If you want to make a game to monetize, focus on making it polished and fun before you try to start integrating ads.
But overall, you have great potential. Be judicious in where you apply your efforts, and you'll be making absolutely astounding games!