What Happens If Someone Registers My Bike?

It's a fair worry: if anyone can register a bike, what stops someone registering yours? The honest answer is that registration isn't ownership — and the system is built so the person with the real evidence comes out on top.
Key point
Registering a bike you don't own doesn't make it yours. It creates a record — and a record you can't back up with a receipt or frame-number evidence is a weak one.
Claims can be disputed
If someone registers a bike that's really yours, you can dispute the registration for admin review. The dispute process weighs the evidence on both sides — receipts, frame number, photos, dates. The genuine owner, with the real paperwork, wins.
Why registering first still helps you
The best protection is to register your own bike early, with your frame number and receipt. Then any later, competing claim is starting from behind — and you already have the dated, evidenced record.
The takeaway: get there first with real evidence, and a bad-faith claim has nothing to stand on.