Those are motorcycle tires (run a rear m/c dual compound tire on the front and a car Run-Flat on the rear)
Ah, a Darksider, eh? For those readers who aren't aware, it's a 'modification' for high miles bike riders, the intention being to obtain far higher mileages between tyre changes via a flat car tyre profile.
Over here in the old world, there are things called corners so it's a distinctly USA orientated thing. Thankfully..
