you mean psi...but yeah, what Mike said. I've got some heavy duty tires to be able to withstand the loads generated by a double-stack and my scooter and they require 80psi. When I just have one boat on the trailer, I drop the pressure down to where I can just see a little deflection in the tire sitting still - usually about 45 lb....er....I mean psi. <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />