Robert,
I have 3 used Rotax Pipe mounts that only attach to the engine side of the frame, which prevents the pipe from bending – in case your pipe attaches to both sides of the frame. I’ve seen many welds around this spot due to this problem, not sure if Rotax legal or not. If you want a mount, $50 plus shipping, they sell for $120. We sold all our Rotax motors.
Thanks
Brian