just installed brand new 315 nto5's . had them at 28 psi and went pull a few holeshots. very dissapointed so far !! had to baby it out the hole at 2 k and slip the clutch then when finally got in it they spun then spun all second ! my completely bald 555r's did better two nites ago. This really sucks. Hopefully they will break in ??? oh and also had little wheel hop that never had before!