Thanks for your drawing! This looks very much like a Jouta to me,
I'll keep your suggestions in mind...
Stefan Bartels <sbartels@xxxxxxxx> hat am 23. Dezember 2009 um
> Dear folks, after a pause caused by illness and hard work I now
> the wheels and materials together to begin building my trike.
> I can do three variants which I made sketches of. In the third
> the seat swings on the beam, the others are a bit more
> Where should I put the hinge? Which design will be most stable and
> an acceptable turning radius?
> All three wheels are to be 20".
> Your ideas and advice would be most welcome!
> And have a happy Christmas!
> address is
i kept thinking about trikes as well. Attached is a drawing with
variants called D and E, extending your version C and keeping georges
suggestions in mind.
In your C version, the rider is sitting completely on the front part,
which means he will tilt to the inside of the corner, shifting his body
mass sidesway an down, which is good. However, i believe ifthe pivot is
pointing forward in an angle this flat, with most of the mass on the
front part, you will experience flip over like behauviour, when
In my variants, i moved the pivot a lot towards the rear. I could be
pointing forward(E) or backward(D). The pivot could even be as close to
the rear axle, as (E), because of the two wheels in the back. However,
this would leave a short distance to the rear axle probably resulting
in poor steering behaviour (big turning circle). So in this respect,
the pivot should be somewhere towards the middle ofthe frame, while
keeping you and your seat attached to the front part. If you neglect
stearing stability for a moment, is should not matter much, whether the
pivot axis points forwards or backwards, as long as the pivot is lower
than the horizontal line between the two wheel centres. In this case,
the pivot lifts up when cornering, resulting in the python like
correcting force of a centre steered recumbent. Since the rear part
does not tilt, due to the two wheel, when cornering, your probably
would want to lean over more. So in a way, you will be facing the
problem of lean-steering at the same time. Whith the angle of the
pivot, you can influence, how much you want to tilt during a given
turning cycle at any velocity - as well as the bevorementioned amount
of pythonlike vertical pivot movement, which defines the correnting
force to straighten the bike.
Therefore, i put in two handlebars attached to the rear part and
pointing forward on either side of the seat.
Grabbing these, you can control the steering while also leaning.
This is my best bet, whithout having build anything vaguely near this
A couple of month ago, there was a youtube video from a french(?) guy,
who had build a python with pivot closer to the back with steering bars
attached to the rear i believe. (Are there actually some drawings