Not sure what you mean by "bar" tires. I put inner
tubes in my 8HP Troybilt tubeless tires. Used 8" tubes bought a a
Goodyear tire store. It's a bit tough to get the bead over the rim but
not impossible. -Olin

Same here, I dont know what you mean by bar tire, but I replaced the
tires on my old 8hp horse and put tubes in them. I dont remember it
being especially hard.

Bryan