All those "gear charts" don't take into equation the riders weight, aerodynamics, wind, traction, track surface..... they will get you in the ballpark, but trial and error are part of the fun. I had someone send me a pm saying my two clones were definetly not stock because of the speed and gearing. SURPRISE! They are and look what they did! The Double Whammy has a 12 in the front and a 38 in the rear. On one engine, it is a dog, start the second one and it's a whole 'nother ballgame.
It's not that great off the startline, but once it gets rollin' she tops out right before the line.