best tire for milage

[77S-Glide]

i ran a car tire on my old hardtals years ago and didn't suffer any ill effects. all i could afford back then was used car tires. lots better mileage too. since no one has mentioned the Conti tires i will. i put a Conti Milestone on my Streetglide about 6k ago and like it. good grip wet or dry and it looks like it's going to last longer than the Dunlop that went 12k before getting swapped to the Conti.
Dick