How to determine efficiency? + Inrunners for direct drive

[nativepaul]

The smaller 3040 will disipate less heat than the 3080 and therefore will have a lower maximum power output assuming the same efficiency.

With the lower wind count/bigger wire of the 3080 its maximum efficiency will be at a higher amp draw than the 3040.

Luckily Lehner is one of the few companies that supply efficiency curves for their motors, so decide how many amps you are going to run then look at the graphs and pick the one with its maximum efficiency in that range.

I know Lehner have made 3080s with shafts out the front and back for a boater who made a twin drive cat with 4x 3080s 2 coupled together on each side, it would have to be a special order from Lehner directly but they are happy to help, I guess Neu would be the same.