I’m all in for a starter generator, I would like to get one.
If your are running the starter/generator off a 23 inch flywheel and with a 2 inch pulley on the starter/generator, that’s well over 7000 RPM. Seems like a lot.
What is the output voltage at that speed?
Is the unit self regulating when charging the battery?
Starter alternators use a standard automotive regulator between the generator and the battery.
They also use a standard automotive relay to engage the heavy load to the starter.
I'm not sure what the max rpm is, but it should be ok at 7000 rpm. On golf carts I think they run in that range.
Hugh Conway's machine has the 23" wheels so he can better comment on the generator speed and output.
On my system the flywheels are 20" and I put a 2.5" serpentine pulley on the starter. The engine runs at 475 rpm so the starter/Gen runs at approx. 3800 rpm. At 3800 it puts out adequate volts for charging but only about 3 amps. Just enough to allow the battery to recover from a start, but not enough to power anything else (except maybe some instrumentation like the Arduino). But that's all I want from it.
Here is my setup as an example...
https://youtu.be/qbcbuygYJdM