Gotta go with George, I have always run 35 on my Minis up to my Pro, never had a problem until this year, I almost did not run at the nats because I broke chains on both mini's. However I ran both of them all year, but I ran all the ARMA races except one, they just flat wore out. 35 if you replace it mid season, or go with 40 all season, just my thoughts.