Dear openbikers,First and for most, congratulation and thank you very much for
the fantastic website you created and all the great information you gathered
there. I also wish that the ongoing crisis does not affect you too much!
Following Steve Nurse advice, I am contacting you hopping you might be
interesting in, and may have relevant critical advices about a recumbent trike
I have been thinking about for few months and hope to build eventually. I have
never seen the design I made (see enclosed or bellow) and I am afraid that the
steering I want to try won't be sufficient... hence the need for support before
investing the little money I have into it ( I am just finishing my studies...).
I am now doing a volunteering work in a farm, hence, I might have the best and
only opportunity to build it before a long while.
I spend quite some time thinking about "sustainable" transportation means. This
led me on the design draft you will find enclosed (and bellow). The main idea
is to have a comfortable and efficient bike able to do many kilometres, ideally
able to take a 60liter bag or more on it, but also "tiny"/"foldable" to take
the train with it and carry it around for potential long trekking adventures
(as well as every day vehicle)... I don't think that today's "folding bikes"
really tackle those criteria...
I dream to build the frame in wood, a material that I really like and, above
all, that I know more about than metal (and I think I will have easier access
to the tools it will require). The rest would be made of off-the-shelf pieces
put together... So far, I plan to use an internal gear hub with paddle break
(nexus 8 most probably, or 7??) in a 26" wheel on the front limiting lose wires
around. At the back, I intend to use a mountainboard technology
(https://www.mbs.com/parts/12203-mbs-metal-matrix-ii-truck-system) with wheels
as small/flat as possible and wheels that can be mounted on (this bring me to
6,5 inch or 8" mountainboard wheels/tire or I need to build my own wheels and
find some 12mm axis hub...). Perhaps a longboard with tire wheels (like Nordic
Roller wheels) would be lighter/more efficient? Initially, I dreamt that this
mountainboard truck would be my only steering/tilting/suspension system, all in
one! But I start to doubt (here are links toward the closest project I can find
https://www.youtube.com/watch?v=j6nIX1dQ-bk and to 3 wheel Frankenboard| C8080
70kv| 12s| VESC| MBS Matrix| Custom 9 layer vacuum press and will try to
contact the person). It is the most critical part of this project and part for
which I would be very grateful for your (or friends of yours in the domain)
I like the idea because I would have very little metal pieces to use, no need
for any steering handle and I would have a kind of tilting effect/advantages...
But mountainboard wheels risk to create quite some drag (I found some "road
wheels but they remain very large) and I am afraid it won't give me enough
turning radius... To avoid this turning issue:- I can use very soft strings
and make the angle of the truck/bike fixation steep but it is a risk of riding
like a fish when I am on straight roads... It might be possible to create a
system to adjust the strengths of the strings at any time while ridding
though... That might be a relevant solution?!
- I can reduce the front-back wheel distance but only within a good stability
Mixing those 2 worlds - mountainboard/bike - is risky I guess and I don't have
any old or scrap material with which I could try a prototype or make proper
measurements before buying the final material unfortunately. I also dreamt to
use second hand material as much as I could but I won't have time for this
unfortunately and the virus crisis does not help neither...
Finally, I intend to split the "front wheel + transmission part" from the
"main axis + back wheel + seat part" in two pieces. The joint would be bellow
the bottom of the rider more or less. Those 2 parts could then be carried
separately for transportation. When disassembled, I would thus have 1 wheel in
one hand and, on the other one, or attached vertically on the side of a back
pack, the "main axis", with 2 "bars" normally used to make the seat just around
the rider's spine now folded along this main axis and the mountainboard truck
at the end of this same axis. Of course, this separation will bring fragility
and/or weight! I could use this "separation" point to create a steering on the
front wheel and thus improve steering... but I don't think pedal breaks on a
steering wheel is a safe idea...
I hope that, thanks to the draft scheme bellow, this long and probably messy
description in my broken English will make sense to you. I am happy to give
more details or reformulate later!
If, one day, this project becomes reality, I shall share it (plans and
pictures) opensource of course!
I would be very grateful to receive your comments if you have the time and the
energy. Do not hesitate to forward it to other relevant riders if you think it
can help (also mountainboard riders perhaps?).
I remain at your disposal for any questions you may have.Looking forward to
hearing from you,
Kindest regard,Matthieu (from France)
(whats'app 0033 782 178 800
PS: I am happy to subscribe to the mailing list!