izeman wrote:LewTwo wrote:Thank you. The bike is probably wimpy by some standards:

Golden Motors Smart Pie version 4 paired with a Lunacycle 52 Volt Shark battery.

Estimated

25 Amps max 50 Amps Max.

The real problem is the lack of an on/off switch short of unplugging/dismounting the battery

*(I HATE that battery)*.

Smart Pie 4 -elect ratings.png

if you use this motor at it's given specs (400w max and a 50v battery) you won't see more than 8a at the battery. if you say 50a max and 50v you're talking 2500w motor power. which of those assumptions is true?

The picture of the specs is from a website that

sales sold this version of the motor.

The 400 watts at 48 Volts is the "Rated Power" not the maximum.

With A 36 battery

*(charged to 42 volts)* volts I never saw it draw more than 650 watts.

I believe the 50 Amp "phase" current is an instantaneous measurement but that would be the worst case scenario.

If the ratios between the rated power and max draw hold the worst I should see is about 800-900 watts which is where I came up with my original 25 Amp max estimate.

(52/36)*650= 938 watts .... I still think that a 25 Amp "switch" may more than adequate.

I have been fighting the Golden Motor software most of the night but finally got the controler reprogramed for a larger voltage range

*(31 to 60 volts, I think)*. Maybe after I get some shut eye I can try to get some actual wattage readings with the Shark battery.

**EDIT:** 910 watts on fully charged shark battery .... and wow what a difference those extra volts make !