GPS Tracking

There are various motorcycle tracking apps out there. some work off cell towers, some work off wifi, etc. Just google motorcycle tracker. That will offer you realtime tracking that you can use to call the cops. but my preferred method would be to use lowjack. They have a very well established rate of recovery, and it is what I get on all new cars.

LoJack For Classics | Best Anti Theft Device for Classic Cars

Sadly I think for a racecar to be stolen, its likely going to be an inside job where someone you know passes the details along. They will likely know when you will be home or gone, so I'm thinking tracking along with actual physical security is a good approach. Fabricate a way to lock the parking brake, or use one of the clamp on car boots, etc. You may not be able to stop them if they are truly determined enough, but you can deter them to the point they give up. I wouldn't exactly classify a car thief as a hard worker..