Weird Speed Limit - Unity and Metr

You should only be getting over 30mph with that gearing on absolute full voltage.

Bet that thing rips off the line and climbs hills like a champion.

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Yes this was the issue. in the end i swapped to 8" tyres and now it tops out around 33 as i was expecting.

The loss in torque is not really noticed, and i just cranked the motor amps a little more to compensate.

Sure does. even with the 8" tyres its got some serious grunt. even at 280lbs i dont notice hills. the Unity handles the power surprising well and never gets hot.

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Motor amps have a more direct impact on torque. Trust me on this Q. Battery will give you gsxr1000 mid range silliness but motor changes the off the line dramatically.

Glad you got it sorted anyway.

yes good spot. i knew this. i wrote a long post explaining this just yesterday. spent so long over the last few days talking about battery and motor limits that im driving myself crazy.

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Its a learning curve to be sure. I only know by doing. Been doing for a while now.

Don’t ask me about anything maths related. (notice how I said maths)
Full Saul on the road to Damascus. How I am. Touchy.

creepy much?

Did you rode one actually?

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when the controller maxes out at 95% duty cycle it means only 95% of the battery voltage gets through the controller to the motor… (less max rpm than bat voltage * kv)

when you are very close to the no load speed you won’t be able to draw as many motor amps as the motor current limit (the motor generates bemf voltage in opposition to the battery voltage, and the bemf voltage nearly equals the battery voltage close to no load speed, and surpasses the battery voltage if forced above no load speed.)