What if the owner of the said bike bought it to be a cruiser and not a performance bike? Is he still stupid if he decides to run a car tire?
Unless owner of said bike can be absolutely certain of never riding in inclement conditions, on twisty roads or requiring any kind of evasive manoeuvre. (But that never happens.) And if he can get his insurance company to state in writing that they're ok with it. (Best of luck with that.)
Makes you wonder why owner of said bike would even want to ride.