When I got my Bronco Roughriders, which are s'posed to be a copy of grizzly claws I ran them a 40psi. But after reading some posts on here, reduced them to 35psi and couldn't realy feel any difference. Last weekend I was having a general look at them and it looked as if the outer edges were wearing faster then the middles so I've put them back to 40psi. If I'm offroading I'll reduce them to 30psi and pump them up when I get back home.