thats the problem isn't it. Most of us need two widely different gear ratios for different uses.
When i'm toolin around the lanes and villages in the Countryside I can rarely get an opportunity to hit 55mph and then its usually only for a couple of minutes at most before you have to change down for a corner or road junction.
For that you need a closer ratio box to get back up to speed quickly without any large gear ratio jumps
Yet when we occasionally need to do long high speed runs for club runs and rallies etc you need a high speed cruising top gear .
What would be nice is a crankcase with a simple drop-in final ratio cog
like you can quickly and easily change your wheel sprocket on a motorcycle
Just thinking out loud here
I wonder what sort of difference to gear ratios you could achieve by fitting a larger wheel with a lower profile tyre like the Ve*pa Lx50 has a 11" wheel rim with 110-70-11 tyre . Clearance to the frame is very minimal as it is though....barely an inch. Not sure how to work out a final ratio or speed
If you fit a wide rear rim with a 4" wide tyre theoretically you'd get an extra 4mph @ 6000rpm ignoring wind resistance
http://scooterhelp.com/tuning/lam.gear.calc.htmlconversley... fitting a 3" wide tyre on a standard rim gives a 4mph reduction at 6000rpm