See USA patent 4925202 & patent Des280309 & patent 4186935 & patent 4408776 & patent 4432561 & patent 4497502 & patent 4526392 & patent Re32681
The Tricumbent Raven at the IHPVA, Just 2 bikes have just aquired the patent and hope to have it for sale soon, here's the Patent. Read a review by a Raven owner, Ross Lowell.
Mark
Stonich
I strongly recommend that you start with about 1/2"
of negative trail. With negative trail on a RWS trike,
any side loads tend to straighten the bike out. The head
tubes on the Walrus are vertical, and the horizontal
pivot for the skates is 1/2" ahead of the vertical
steering axis. When cornering at high "G"
loading you can let go of the bars and it will quickly
straighten out.
With wheels instead of skates, you could get negative
trail just angling the straight forks back, but that will
induce some wheel-flop. You could get strong self-centering
action with the forks angled foreward (conventionally)
and enough rake (fork offset) to get negative trail.
You can check out the Walrus @
http://www2.bitstream.net/~dkrafft/icebike/icepics/ston09.JPG
http://www2.bitstream.net/~dkrafft/icebike/icepics/drags00.JPG
Mark E. Stonich
Minneapolis MN USA (612) 824-2372
Minnesota Human Powered Vehicle Assn. - Twin Cities
Tandem Club
MnHPVA Web Site; http://www2.bitstream.net/~mstonich
Tuesday, 24 July 2001