I agree, w/o the sides & tail I suspect a fairing would be mostly for comfort - which ofc I've no aversion to lol... yet seeing the above pic has brought another concern to my attention & one I'd not considered before (thanks BTW), & that's weather - most particularly side gusts.
While the above body shell no doubt vastly reduces wind resistance under ideal conditions & it's hard to tell from the pic how tall it actually is - I can't help but wonder what effect it had on handling & control, say w/a variable 20mph crosswind for example... a phenomenon not uncommon at all on the coast of Maine (to be guilty of a grave understatement heh). While I think I'd have some advantage over the above (what appears to be) bicycle with the lateral stability a trike provides... I think perhaps I'd attempt a more "form fitting" body, reducing it's profile as much as possible.... which granted, my not be possible at all.
Unfortunately yes, my pedal chain takes a somewhat convoluted route & worse yet it's redirects are on the power side. After many admittedly silly attempts to pass it
through the A arm suspension (to try and increase ground clearance), I resorted to blatantly copying the chain path used on an unsuspended taddy. As I've that great honkin' engine case in the way - I've little choice. It's only a lil 49cc four stroke, but as it's an auto clutch (I've already too many levers and whatnot lol) it's somewhat wide (11").
I do appreciate the link to the V belt pulleys as it seems the second ya seek "recumbent" bits, the price triples regardless of how basic the part may be - strikingly similar to "marine" or "aviation" stuff it seems lol, I took another option however and one that's seemed to work really well. Despite the fact my "clicky" research informed me that I should use cogs on the power side (to reduce the felt vibration of links passing over a roller), I simply got some inexpensive skateboard wheels and lathed them down to accept the chain & replaced their shoddy bearings w/some quality sealed ones I happened to already have. I'm planning on getting some better skateboard wheels at some point, a softer compound (again, reduce felt vibration) yet at the time the cheapos were all I could find locally & as I'd never attempted to lathe skateboard wheels before - I figured these would be good enough for my experimentation.
As it turns out it worked really well, with the teflon chain return tube, 'Starboard' (fancy overpriced plastic, same as a cutting board tho) chain retainers & tube supports and the new route - I can now pedal and back pedal freely w/o binding or undue friction... ofc there's some friction, but the pedals will free spin a couple of turns despite the chain being bone dry.
I'm thinking there will be far more drag from the jackshaft & engine chain (clutched) than there is from my two pedal chain idlers... yet this "pedal assist" motorized trike differs a bit from others in that I hope to pedal to assist
it as opposed to it assisting me, should somehow two out of it's three motive systems fail leaving only my leg power... well, I hope I'm not
too far from home lol - it's heavy for a tadpole trike if nothing else. It still weighs in less than a factory new two stroke Tomos moped however, something I'm perhaps disproportionately proud of - and I can thank it's LifPo4 battery packs & (double walled) aluminum wheelset for
Here's a coupla pics of the idlers while I was making them, I may redo them as I can squeeze a hair more ground clearance if I remake the Starboard & stainless bits... but it'd be fractional at best *shrug*