I've had a go at a calculator to visualize and trace gear ratio / rpm / shift points etc. (for rev heads only)

http://www.blocklayer.com/rpm-gear.aspx

There are tacho and speedo gauge diagrams side by side. Enter gear + diff ratios and tyre diameter, then drag the RPM slider to animate the gauges.
Click the gear buttons to change gears, and set a shift point (RPM) then hit Auto Shift to run up through the gears, shifting at the shift point and recording RPM and KPH at the shift points.

Can be fun to play with.

Anything else needs adding to this? please let me know.

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