Here’s a gear calculator sheet I made for the SSE. If you recall John Denman’s one for moto, this works the same way, but with the 175 ratios (Of course)
Just make a copy to your google docs to play with it.
Screenshot
I found some axle sprockets all the way down to 18t, should give some more gearing options. Thing about the special chain isnt ideal though.
Now you’re cookin’
122.6
Still guessing on the shift and overrev RPM
A 20 motor sprocket is a standard offering. Looks like its more than safe to not run out of gear options