In an attempt change gearing, has anyone tried Twistgear made by Johnson Engineering in Iowa? Their website, Harley davidson parts, gear ratio, motorcycle performance parts, overdrive transmission is informative and extensive. Main items which replace stock are trapdoor bearings, a more robust countershaft, helical main gear and helical fifth gear. Not sure exactly how it works, as my knowledge on all things mechanical is not great. Supposedly, TwistGear provides 10% more gear box, which can be used several ways. If you only install TwistGear, then 1st through 4th will go 10% slower but with 10% more acceleration than current setup. 5th gear rpms will stay the same. Adding one tooth to the transmission pulley, gives 7% more torque in 1st-4th but 5th gear rpms will be reduced 3%. For top end speed/low cruising rpms, change the final drive or primary drive ratios 10% so that 1st-4th stays the same as current setup but 5th gear drops the rpms 10%. Cost for the product is @ $500.00.