What battery are you using?
According to Calc RC - (Hitmoto EMXT, same truck) your gear ratio is 2.920, FDR with 26/64 is 7.188
http://www.calcrc.com/downen.htm
running 26/64, 2s lipo with a 2500kv motor, 4.75 inch tires(a guess on my part) should get you roughly to 40mph.