More importantly: its VIN number has been recorded in a database that is part of international cooperation agreements, and can be traced back if stolen or re-registered. Race bikes may not even have VINs!

Almost certainly not a carnet, but possibly some form of TIP or other authorization paperwork.

Note that when you transport your Canadian-plated vehicle by aircraft, the vehicle gets placed in a customs warehouse at the other end. And to drive it out, you - the owner - must show up, with your passport and your ownership documents, and sign papers whereby you basically promise to take the vehicle out of this customs area within 12 months, and not sell it on while you're here.

So yeah, transport by commercial hauler to a customs warehouse and then pickup by the owner = minimal paperwork. Transport of other people's vehicles in the back of a van... *potentially* more paperwork.

Real-life example: leased vehicles entering Russia. I live in an EU country with a land border with Russia, and this is definitely A Thing. When you privately lease a vehicle, the bank owns it - you (and maybe a couple of your family members) are simply an Authorized User written into the registration certificate.

This is fine for driving the vehicle all across the EU/EEA and most "friendly" countries, but at some point Russia decided that it would treat any border crossing by a non-owner (even an authorized user) as a potential attempt to import the vehicle, and require a full customs bond from the bank that owns the vehicle. Which a bank - technically owning thousands of vehicles - of course wouldn't do.

So yes, there was a legitimate problem where you could not cross into Russia in a leased private vehicle without loads of paperwork and putting up loads of money. It CAN happen, and the UK is now a third country, as much as Russia.