so i found out yesterday that there's a track about 20 minutes from me (trilogy bmx in pottstown). 2 questions on setup... i'll need a new sprocket (currently running 25x9) so i don't spin out before the first turn, and some tires (current ones are some old near bald street/park tires that need replaced anyways. what's a good sprocket size to jump up to? not sure what a good ratio is for a bmx track. and what are some good dirt/track tires?