we can only speculate why FM limits power - could be cost, could be fear of not meeting regulations (trying to fit into the 750W PEV limit), could be because it’s designed for the worst case dumb user and to avoid lawsuits, could be a combination of the above… but why VESC has more is simple:
- brushless motors always can deliver more power than they’re rated for as long as you keep an eye on temperatures
- low end torque is limited by the controller, not by the battery - so a stronger controller can easily produce more low speed torque with the “same hardware”
- it’s a DIY community so many people are happy to accept smaller safety margins than they maybe should (even though FM seems to have questionably small margins as well recently, see 120V mosfets on 113V board on the GTS)
- lastly any speed increase from a VESC controller is mainly because we can change whether/when/how pushback occurs while the true top speed of the motor is still dictated by the battery (this is why XRV’s don’t let you break speed records set long ago by XR riders)