I sold my Goki setup about a year ago for $1000. It sold right away. So yes they are very valuable. But this was a complete setup in darn near new condition. They work "ok" when installed properly and use the right battery. If they are not installed perfectly they will just destroy themselves. And there are 2 different ring gears, one for the 85 and one for the 86. The ring gear has to be set up right. Kind of like a rear end ring and pinion on a truck. Also you MUST have a working de-comp system on the trike. If you have the side cover and the ring gear you can piece together the rest. The starter from a snow mobile works. I just don't remember which on I used, and the charge wire (yellow wire) can be made up if its missing. It just has an inline diode to switch the power from A/C to D/C to trickle charge the battery using the lighting circuit. I sold mine because it was just to much of a pain in the butt to keep everything working perfectly. Starter shafts and the ring gear are deffinatly the weak links in the system.
YAMAHA 450 HYBRID
85 350X- RED
85 350x -BLACK
86 350x-WHITE (with Goki)
85 250r
83 atc 70
84 atc 70
84 atc 110
09 yfz 450
2006 Arctic Cat Prowler
RZR XP 900