It may never have existed. I remember something about HPEVS reporting that one of their motors had been misrepresented by some reseller with a different number and false power claims. The "AC-41" might actually be some other HPEVS motor model. Have you asked HPEVS? Is there a manufacturer's information plate on the motor?Anyone out there have the specs and graphs on an ac41 it seems that it doesn't exist in nature note do the specs