I guess that Torque is maybe not the best metric because it doesn’t account for wheel diameter.
Torque (Nm) = Force (N) * Distance (m)
If we compare my builds to @tenshi0’s we both have same Voltage, motors size / kV.
My build has 2.85:1 reduction producing 22Nm Torque but with a 90mm wheel that is 490 Newtons of force.
@tenshi0 has 4:1 reduction producing 32Nm Torque (50% more) however with a 8" (203mm) wheel he only gets 215 Newtons of force (55% less).
With these builds the board with 50% more Torque actually produces 55% less Force to push the user forward.
I think @ZachTetra is right that we should think in terms of acceleration.
Acceleration = Force / Mass
For me that means 490N/150KG = 3.2m/s/s forwards (1/3 gravity). During this acceleration im experiencing 5% extra gravity and an 18 degree shift forward in my balance.
If my 70KG friend tries out my board then for them the same board accelerates at 7m/s/s forwards (70% gravity). During this acceleration hes experiencing 22% increase in gravity and an 36 degree shift forward in balance.
Personally i think that Force is the important thing when considering overall gear ratio to the road, but its the acceleration that throws you off. Thoughts?
EDIT: just did the maths and using the calculated 3.2m/s/s acceleration at full power my 0-20mph time should be around 2.8 seconds. Feels about right . . . Ive only ever been brave enough to do it a few times. For my 70KG friend he would be able to do the same 0-20mph in 1.24 seconds . . . assuming he had enough grip to put that power down and could hold on strong enough.