Why not make variable voltage system?

[regmeister]

I forget the reasons why 4-speed didn't quite work for me. But I imagine reducing component count and number of connections was high on the list. Here's the proposed relay / diode layout.

Relays are the circles in the sketch. There will be another contactor and kill switch, not shown.
The diodes I am using are these. Haven't given much thought on keeping these cool. Was planning to bolt them to 3/4"x1/4" copper.

I'm thinking I don't require fine control. The prop is not boat, it is for a wing. Same as this. Full speed at all times

 

[regmeister]

I see my link was wrong earlier, as the page has frames. This is the one I wanted to share.

http://www.sunrise-ev.com/controllers.htm