Rotoflex coupling to connect motor to tranny

I was planning on using a rotoflex to connect my siemens electric motor to my transmission. The simenes motor has a hollow shaft, so I would have to machine a coupling or modify a stock coupling to fit and weld to the siemens shaft. Since there is some flex, I don’t need to be super precise when making my engine adapter. Im hoping this will cut down on noise too.

I know the rotoflex couplings are typically spinning at around 3500 rpm. Do you think it would fly apart if I spin it at 9000? Keep in mind it would be positively located on both ends with bearings, and not supporting the weight of a driveshaft. Plus it would be transmitting about 1/4th the torque since it is before the the differential and transmission gearing. It would be pretty easy to fabricate the interface to this rotoflex coupling.

Figured I’d check to see if anyones done this and had problems before I start fabricating.

from what (not a lot) I know about electric motors… you are going to lose a lot of torque and risk over-speed spinning the motor up to 9,000 rpm. You might be better off designing a more elaborate adapter allowing you to retain the clutch and tranny.