(2) HV4.5 motors 1 is considerably slower. Worn out rotor?

[suicideneil]

I had the same thought a long time ago- it clearly is a 5mm shaft that has been turned down to 1/8", but I didnt realise the signifigance until I joined up to this forum and learned of motors with 5mm shafts. Its scary how much I have learnt from RCM, and even scarier is how weak this old rotor is- the new one is such a great improvement, tons of bottom end torque from it.