Yup, 4s would be better or else you'd need a large 3s pack. I think that 2500-3200 mAh 4s packs are probably ideal. About 600-700W on a 10" prop - the design won't accommodate much more than a 10.5" diameter so one needs a high kV motor as is the case on most classics with trike gear. Oh..., no, we're not allowed to convert them to conventional - it's just not honorable...
Ralph's build should turn out just like how I envisioned it. I made no provisions in the kit or the plans for fixed gear not that it is rocket science to do if one wanted to.
I'm going to direct Michael who bought a kit for e-power to the thread. He might have some further thoughts on the subject. I did alter the e-version slightly so it should be a little lighter. I'm thinking 48 oz dry, 56 oz "wet".
Looking forward to seeing that stab come together Ralph!
David.