I live in a state that has 80 MPH speed limit. When riding at that speed my RPM is definitely much higher than it needs to be. I would like to have an overdrive 6th gear.
Question ?? Why did you choose 2200 RPM at 80 MPH as the target RPM/Speed numbers ? Is there a benefit at this RPM as opposed to using something in the 2300 to 2600 RPM range for 80 MPH ? Would the peak torque RPM be a good choice for the target RPM at 80 MPH ?
Unfortunately the Rocket transmission is not a 6 speed with 1 set of gears just left out,,,, it's a 5 speed that happens to have 2-3 bits out of a 6 speed already in it (6 gear + N positions on the detent wheel, 6 + N positions on the GPS, and a blank space on the selector drum above 5th).
So there are a lot of constraints that really limit the options.
E.g. when it comes to effective RPM drop & top speed, the input and output shaft centres are fixed, so the sum of the paired cog pitch diameters must be equal to twice this shaft centres distance, also the gear module has to be the same so teeth will mesh.
The 3 feasible options I came to conclusion of;
(a) this option calculated to give
2200rpm at 80mph, i am sure it will work although there are a number of challenges
(b) this option calculated to give
2700rpm at 80mph, i am also sure it will work, and less challenges than option (a), doesn't drop the rpm as much as I'd like/not enough to make the job worthwhile
(c) this option is sort of a happy medium between (a) and (b), calculated to give
2400rpm at 80mph, which is satisfactory, however... it is venturing too far into the unknown.
Hence I picked option (a). I might develop option (c) in parallel to see if it'll even work, but the focus will be ion (a).