In truth I'm guessing but my first guess would be that it works sort of
like a 3-way light. You are energizing different motor windings from
the switch. Some speeds might be the combination of several windings.
That would explain what you are seeing.

Huss Mohrens wrote:
In article 7eSCg.625$Ch.72@clgrps13, "Kel" wrote:

I bought a used Minn Kota 65C, and only 3 out of 5 speeds work. 1, 4,5 work
but 2,3 don't. The previous owner replaced the rotary switch but it didn't
help. I'm not sure the switch is wired right and I tried switching a couple
wires around and all positions work on the switch but still only 3 speeds.
Any ideas? motor itself? Not sure exactly how these motors work.

Most likely the cord that goes down to the motor.