Originally Posted by captdramamine
My goal is to raise the top speed of the bike without lowing the final drive ratio (sprocket).
Taking this & your original post together then, what you really mean is you'd like to optimise gearing for the highest top speed.
(Unless both of us have no clue whatever what it is you're after
This means that the gearing must coincide the maximum power rpm of the engine with the maximum roadspeed which that power level can just, but no more,
Gearing choices like this are normally decided* by manufacturers by overlaying rear wheel power curves (at various ratios) on a graph of the vehicle's combined rolling & wind drag vs speed (a 'square law' curve).
But this get's tricky on a bike. The biggest factor is wind drag, but this changes significantly with different riders/riding gear/riding position & even different accessories such as mirrors! It should be obvious that fairings & windscreens can make huge differences - and in either direction, improving or worsening drag!
So that's your 1st thing to decide...you gonna be flat on the tank in riding leathers or flapping about in the (slower) breeze?
Then you need to guesstimate (not having any manufacturers or test data much) what speed you think the max power of the bike should
be able to manage overcoming that drag.
Then another estimate/assumption needs to be made. That the rpm quoted for max power is actually the 'optimum' revs. (It would be close anyhow.)
Sooo.....put simply, with (stock) max power quoted at 8k rpm & knowing the speed you believe is possible in the conditions etc. you chose, that then gives you 'optimum' top speed gearing, however you choose to achieve that via combination of primary drive, g'box & secondary drive ratios.
*I actually did this as a placement student for what used to be Leyland Truck & Bus in a previous career incarnation!