I guess you haven't seen the vids on the indoor coke syrup racing then? If you would have seen those videos, then you would be out in the garage right now. They run go kart wheels and tires and usually some old school or custom copies of the old hub adaptors. No rear shock, just a solid, but adjustable strut bar. Most have special nerf bars as well. There was a company called Missle Industries, that not only did a 3 wheel to 2 wheel conversion for several different trikes, they also made flat track kits and parts. Get to searchin and it will blow your mind.
Nicholson 500x (Project)
Nicholson 185s
Nicholson 110 (That takes an atc70 tank)
Ascott 500 head/350x (Project)
Homebuilt Racer Chromoly Suspension 110 (Ragin Runt)
PK Racing Suspension 70
A+ Inc Suspension 70
AWS Aluminum 90 frame
Hi Performance ATC Suspension frame rd350
Hi Performance ATC Suspension frame 90