Hi all! Im working on two parallel projects, both a velomobile with tadpole configuration. One is single seater and the other is for two riders.
I will build them one at a time tho, but since im merely at the planning stage yet, i will discuss both projects here.
I have never built a bike before and have very little knowledge regarding the more technical side of trikes, but im stubborn as a donkey and simply cannot put a idea to rest before i explored all aspects of it.
So the idea is to build a fairly light touring velomobile, mainly from fibre composites, with some metal to bolt the wheel assemblies onto.
I have been trying to get my head around the steering mechanics, and found some interesting articles covering ackerman angles, caster and so on. Its all new to me, but i think i got the basic idea at least :)
But im having some doubts relating the "normal" front wheel solution, with a kingpin and only one sided support for the wheel.
Im concidering using normal bike front wheels and use forks from bikes instead.
That would make it easier find replacement hubs, fit brakes, mudguards and so on, but does it have a negative affect on the general handling of the trike?
The two-seater velocar is supposed to have shock absorbers, but in order to keep the track width down, i simply cant use a wishbone car-type shock absorbers. so using front wheel forks with shock absorbers would be easier for me to incorporate into the design.
Another thing is the drivetrain on the two seater.. Im planning on putting the seats next to each other, to sacrifice track width, but gain a shorter vehicle. But i want individual gear selectors for both riders, aswell as freewheel functions on both. ..so both riders can rest at any time, independent of eachother, aswell as picking the gear that fits their individual needs/prefences.
This creates a bit of a problem tho, to link these dual drivetrains onto a single rear wheel.
Im concidering using a internal geared rear wheel hub connected to the crank assembly and bolt a "output" cogwheel on the hub itself and chain it to a tourqe tube that connects both drivetrains. Then a central cogwheel would connect to the rear tire with a long chain.
The frame of both vehicles are bathtub shaped fibreglass with a foam/wood core and single sheet fibreglass removable top. Im curious tho, will fibreglass flex too much for the pedal assemblies/chain drives? would i need a full steel frame?
Im still investigating window materials, so if you know of any plastics that are clear and easily formed into complex shapes, please let me know.
..forgive my lack of technical vocabulary, english is my 3rd language.. :)
So what do you guys and gals think? Are there any issues with my plans? Do you have any suggestions or hints for me to concider? |