Hi Guys
RG7s/Portescaps/Escaps have to be split into the 2 components. The gearbox, which is poor, and the motor, which is still one of the very best available. The movement of the the nylon initial drive is a recognised problem. In fact, if I have an RG7, I move the nylon gear on the shaft to give optimum mesh/minimised whine. A fraction of a mm movement can make all the difference to noise levels - very important with a sound chip.
If you do have any spare motors, get ABC to fit them to one of their gearboxes.
Richard