the thought behind it is using all of the RPM band....if youre bike doesnt make enough hp to redline in 6th, then its wasted rpm....why do 150 max speed at 10krpm, when you can do the same 150 at 12k and have better acceleration everywhere else....essentially youre picking up acceleration, and not giving anything away up top because your bike wasnt using all of the rpm range anyways....i will be doing the same, my cb wont redline in 6th, i plan to change the gearing....if shes done at 150ish, id rather be at redline at that speed than below, if it means picking up some much unnecessary, yet quite fun, bottom end grunt