I've got a trike coming that has a 20" rear wheel. From what I 've read, you can't use the gebe drive system on it. True? Work-arounds?
Re-reading (and re-emphasizing my fading eyesight), I note you said "trike"...
Motorizing Trikes is going to be very important in the future, especially low to the ground like your, with 20 inchers, BUT before ordering any kind of kit, it would be great to hear more about the trike, especially what kind of braking system it has.
Those expensive Worksman have calipers in the front/ coasters on the rear and a parking brake.
I am getting very leery of depending on front brakes only, like those two cheapies I built (the Velo and the Ted Williams).
However, having the engine under the saddle, like the R/S Subaru/chain drive, with remote 96 oz tank in the basket seems right now the most do-able system for a trike.
With GEBE I had to reverse the position of the front brakes, from in front of the forks, to "behind" the forks, so it wouldn't interfere with the mount/strap and belt.
Not as important on the Worksman, very important on the cheapies.
Because, if there is only one set of calipers, the position swap seems to be a "negative" for effectiveness.
It's hard to describe in text, but the engine tugging foward, with the single system of brakes/pads behind the momentum, you really have to have a LOT
of lead time to stop.
I think it has to do with those pads facing upwards after I reversed the position, making them hard to keep aligned on the rim.
What model have you ordered specifically?
A little info early will probably pay off immediately for you, and others, I just don't want to mislead anybody in these early stages of tricycle motorization.