Hi
A few days ago, I added a rear suspension fork design to thingiverse. This design makes a recumbent bike which is a variation on a leaning recumbent trike which is already documented on thingiverse.
The fork is an adapter which sits between an 82.5 x 28.6 x 2.3mm wall aluminium beam and a 20” bike wheel. It includes suspension and consists of a steel frame, 3d printed sliders and suspension blocks. The fork may be slightly harder to build than the trike, but it is lighter (4.5kg for bike version, 5.9kg for trike version) , and should be more aerodynamic and have less rolling resistance.
Note that this design is particular to one bike, but its design principles can be applied to different size beams.
I think parts of the fork could be made using 3d printing in metal, and this would make an interesting project. For example the central join could be made in titanium as a lighter, more aerodynamic alternative to the chunky steel I have used.
References:
Tilting trike design: https://www.thingiverse.com/thing:4201871
Hupi Article on Designs: https://hupi.org/HPeJ/0031/0031.html
200k Audax ride on the bike: http://modularbikes.blogspot.com/2022/08/winter-surf-2022-done-and-dusted.html
Some discussion on Wisil recumbents with pics of a few comparable machines. http://www.wisil.recumbents.com/forums/topic.asp?TOPIC_ID=13024
Regards
Stephen Nurse, Melbourne Australia,
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