Motor/Controller watt ratings, what they mean.
- Thread starter wesnewell
- Start date
999zip999
100 TW
Yes because it can be laced in standard rims.
The watts rating on a motor by convention are mechanical watts output (neglecting heat output). State law that I have seen only mentions watts, not what kind of watts, & only the watts of the motor, without any reference to its load or application. Thus the watts of the motor should be legally determined with the motor in a vice on a bench, no external load. If you run the motor to wind out, top speed & check the amps drawn, you get input watts, which must be less than output mechanical watts. & those watts will be less than start up watts, where watts & torque will be maximum; fastest speed should be minimum watts. Output mechanical watts can be measured by torque times speed. But torque will be minimal at fastest speed. The issue with eBikes is this 750W limit, which seems all sellers ignore, as it says LESS THAN 750, but while "750 Watt" rated eBikes are common (technically illegal watts) , you never see 749 Watts (legal watts). What is wrong with these sellers? Can't they come up with 749 watt motors? But I suspect that a bench test on a "750 Watt" motor would be less than 750 Watts, even tho it is input watts. Has anybody tested this (run motor wind out to top speed on bench, & measure amps, & multiple amps x volts? -IMHO
Have you checked out the simulators at ebikes.ca?
The data it's based on came from testing the motors listed in it.
There's also another page on that site with some helpful info about the futility of motor watt / power ratings.
There is info scattered around this forum about the EU rating system, and how the tests are required to be done to rate the motor for continuous power. It only applies in the EU areas that that rating system applies, but it's probably a good testing method.
Regarding the "750w limit" that depends on when and where you are--some localities have no limits, some are lower, some are higher, some have multiple classes with different limits, and some places they're completely illegal or are all considered mopeds or motorcycles, and laws change over time as well. Which specific locality's limit are you referring to (a link to their legal definition / transportation code will help).
The data it's based on came from testing the motors listed in it.
There's also another page on that site with some helpful info about the futility of motor watt / power ratings.
There is info scattered around this forum about the EU rating system, and how the tests are required to be done to rate the motor for continuous power. It only applies in the EU areas that that rating system applies, but it's probably a good testing method.
Regarding the "750w limit" that depends on when and where you are--some localities have no limits, some are lower, some are higher, some have multiple classes with different limits, and some places they're completely illegal or are all considered mopeds or motorcycles, and laws change over time as well. Which specific locality's limit are you referring to (a link to their legal definition / transportation code will help).
Similar threads
