Pete chain line alignment issues, given enough width between the chain stays for two chains to clear both stays and the wider tire & wheel combination, should not be much of a problem. Initial setup & ongoing maintenance of chain tension through the complete rotation of wheel, three chains & six sprockets mounted on two separate and articulated frames during each complete suspension cycle isn't quite as simple & keeping that initial adjustment during even light & well maintained usage will be problematical. The three chains will stretch and wear at different rates, even using high quality chain & sprockets...pedal chain gets the least pressure placed on it & little wear ensues. I've solved these issues as an after thought (the hard way) & by design (easy way) & both involved the use of spring loaded idlers. I'd suggest finding the room for three hairpin spring idlers, either after market or design your own (the primary chain idler I've usually fabricated) perhaps you'll not use any of the three initially or ever, but on your setup I'd bet you will eventually use all three & be grateful you took the effort to plan for their employment up front. On your setup the primary would seem to be the one requiring a bit of ingenuity, while the other two could simply bolt to the chain stays. Some don't like the look of an idler and some (usually the same who don't like the look) will caution that an idler can rotate into the wheel. My answer to the latter complaint is to use the short style spring idler that could rotate 90 degrees and still not reach tire or wheel & mount it correctly on a straight chain line. Easy insurance. My Simplex has four idlers (the hard way) & now zero chain problems, maintenance & wheel changes are a breeze. The chains runs free and noise is greatly reduced as well.
The tail drag stand is the simple route and really secure. I too prefer the drive off stand but would require some extra effort. From the photos it appears the jack shaft plates have a small area for a horizontal through bolt and a custom (perhaps curved) drive off stand. Even a leaning stand, my least favorite, would be best designed sooner than latter. You are in the home stretch structurally! Just some random thoughts Pete 'cause I'm really liking where your're at with this build regardless of your future solutions. Rick C.
