Hello Everyone.
I finally managed to sail my Drumbeat of Devon which is under renovation, having installed twin 775 12V motors and with a new 12V 5Ah battery.
I was very happy with the extra performance – a bit over scale speed at full throttle.

I managed to get 15 minutes out of the battery by only using full throttle sparingly. I'm planning to install a second battery through an Action Electronics P103 Parallel Power Board for extra run time.
Thanks again for all your advice.
All the best,
Paul.