For those that want to know; mph=(rpm x tc) x 1/( 1056 x r1 x r2 )
a 235/70-14 is about 85inches, so let tc = 85
r1( diff. ratio) is 3.73, r2( trans. ratio) =1.0
so; mph = (rpm x 85tc) x 1/ (1056 x 3.73 x 1.0)
so; (65mph x 1056 x 3.73 x 1.0) x 1/85tc = 3012rpm
or (4500rpm x 84tc) x 1/(1056 x 3.73 x1.0) =97mph
x1/ means "devided by", cant find that sign on my board.
