Has anyone ever heard of running tennis balls (27 of them) intead of a tube or spending the money for Moose Bibs. I meet a guy who rides expert in the Desert and WORCS series and he swears by them. He also plays on the Moto track as well He changes tires and balls every second race One to two months. He says even when he blows 1/2 of the balls the tire is still firm. He runs them front and rear.