Death Wobble. I'm out of commission...

Alas, at this time the Twike is completely inoperable due to a strange death wobble that occurs when hitting bumps or steering back and forth suddenly, even at slow speeds the front wheel and corresponding rudder vibrate back and forth (left & right) violently.  I have replaced all 3 shocks and inspected for loose fittings and I'm still no where.  I'm running out of hope!

UPDATE!  Its fixed!

It was the bolt that connects the frame to the fork.  (Thank you so much Ralph!) There is a nut underneath you can secure with a 19mm socket if you move the splash guard out of the way.  The socket can wedge itself against the shock so you can turn from above w/o it spinning.

An adjustable wrench will get in there, set it to 19mm.  I put a lot of pressure on it and got it really tight.  It acts as a dampener, after this was tightened the regular dampener is not needed.  So if your steering starts developing really light back and forth, meaning there is no resistance / dampening you need to tighten this nut.  The nut head had marks on it like this had happened before.  Now what else needs tightening?