Granpa

Uhhhh, bitumen is asphalt. Usually, it's referred to as the sealed asphalt on parking lots as opposed to the stuff on streets.

However, the stuff that's been posted should get you started. Specific tire and insert combinations depend on too many variables for anyone to give you the exact combinations. If you notice, we've all been sort of general, but that should give you enough to start on your own setup. Heck, that's the fun of it any way.