Orbea alma 29er with rigid Pace fork, notubes ZTR355 rims, notubes sealant, and Racing Ralph 2.4 on the front and Kenda Karma 1.9 on rear. I am 165# I have only a couple of rides and am at 20 psi. and wondered if I should try anything less. Next race is a lot of hardpack, some single track and a lot of rocky/rutted trail. Any comments would be appreciated.