...I opted for a 6 speed progression, using 0 set up not as 0 motor but starting at 13 adding 17.4 to each subsequent level. I actually found a linear progression to offer the most even advancement in power levels.
As another person noted, if I want 0 assistance I can just turn the bike off.
Now, each bump up of assistance results in a noticeable but gradual and even progression imo.
Perhaps there is a logarithmic scale of some sort already built in?
Anyway I liked your theory but in the real world, found linear works best for me.
The numbers you're entering are percentages of amps. Power (watts) = Amps * Volts, and Volts is basically constant, based on your battery. So, I don't see how there is a built-in logarithmic scale if you don't make one. Note that the percentages all get multiplied here:
Motor actual current = Basic_Tab->Limited Current (Amps) * Basic_Tab->Assist_Level_Limited Current (%) * Torque_Tab Current(%)
Torque_Tab Current is calculated from:
• Actual Pedal pressure is fed into the Delta Voltage table to arrive at a voltage that's Base Voltage plus whatever ranges are fully encompassed in the pedal pressure plus whatever scaled voltage is in the range containing the pedal pressure.
• That Voltage is used to re-map to a Calculated Pedal Pressure.
• Depending on the Wheel RPM, one of the six columns is used
• Within that chosen column, the Calculated Pedal Pressure is used to map between Start(kg) and Full(kg) a similarly proportioned amount between MinCur(%) and MaxCur(%).
• The resulting percentage is the Torque_Tab Current(%) in the first equation.
So, at any rate, all we're doing here is changing the percentage of current being sent to the motor, so if that's linear, the power output from the motor should also be linear. What you're experiencing is a linear increase in additional power with each higher level. The power jump from 17% to 35% is a doubling of the power, but the power jump from 87% to 100% is only a 15% increase in power.
If you wanted to experiment, you could make MinCur(%) and MaxCur(%) the same (choose something like 50%) to eliminate torque / speed effects, and then any pedaling should produce the same percentage out of the Torque Tab and so any changes would be solely from changing Basic Tab levels.
That all said, you gotta go with what works best for you.