You are mostly correct.
![Smiley :)](https://goldenmotor.com/SMF/Smileys/default/smiley.gif)
The right side wheel does in fact "drive" the trike, but the brake is more towards the centre:
It's not "powerful"; more just slows me down. If I want to "lock 'em up", the front linear pulls could send me over the handle bars...lol
The left rear wheel just spins freely... (likely what you meant anyway - I'm not very well versed in such things).
No, it's not the top speed that I'm concerned with at all. 30kph would freak me out (plus trikes do handle slightly differently - takes some getting used to).
![Tongue :P](https://goldenmotor.com/SMF/Smileys/default/tongue.gif)
It's the amount of actual power available though, and hill climbing ability that I'm most concerned with.
The bike (trike) already weights a lot. Add me, and we're pretty much already at the 200lbs mark. Also, has 24" wheels. Both would affect top speed, I believe...
I just need to be sure that there'd be enough power to move the thing...lol
When I walk, I hobble along at 1kph avg, so 15kph seems like lightning.
![Tongue :P](https://goldenmotor.com/SMF/Smileys/default/tongue.gif)
If a 24v would provide ample torque, then for sure (batteries are not inexpensive).
I BELIEVE it's 32kph max on the street here (Ontario, Canada) anyway. I'd likely never go there.
![Tongue :P](https://goldenmotor.com/SMF/Smileys/default/tongue.gif)
I'm truly very grateful for the advice, Bikemad. I'm presently watching Smart Pie vids on YT. HA!
Again; I really know very little about electronics and bicycles, but I do have a science background, so get physics, chemistry, and math.
![Tongue :P](https://goldenmotor.com/SMF/Smileys/default/tongue.gif)
I feel like I'm in the a good place to learn as much as I can though, and waiting until spring would allow me to stagger purchases (LiFePO4 batteries are up there eh?)
![Smiley :)](https://goldenmotor.com/SMF/Smileys/default/smiley.gif)