Since I had access to the wheel first I will tell you what I have seen. First off comparing a single motor with both aluminum and steel wheels. The motor is forced to lug more with the steel which causes a higher amp draw as the motor is forced to work more. I even noted that a 21.5 USGT spec motor is forced to work harder. I honestly feel that the aluminum wheel wasn't testing these brushless motors well at all after seeing the data.