Hello, Paul!
I spent some time "designing" my second quadracycle, a little on paper (sketches made by hand and pencil and future use of geometric tools and knowledge) as I do not know any computer planning - or in my mind (which is easier, but not more accurate)… According to old German practise and theory closer to us in two centuries, we in Serbia (or old Yugoslavia) consider "design" more as artistic shaping of already generally planned industrial or DIY products... and more use terms that could be translated as planning, projecting and even constructing - just for the first phase of process (in our mind, on paper, or on computer)…
When I figured issues of posting pictures to Forum, I shall publicise some photos and sketches, just for illustration of my dilemmas and questions. Later, maybe some of the planned solutions. General idea is to use as much of components that I already have and make simple, cheap and quickly build quadricycle.
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I was following old Atomic Zombie web-site and found may interesting ideas and solutions, but not use many of that - built my first quadricycle in way that I always wanted, with some inherent issues, so that I abounded it a few years ago, almost finished. Do not like it too much anymore.
You are right, even when members run their topics to the end of construction (many left projects in a way) - there are no stories about experience of testing and using them. Especially, it is useful to discuss mistakes and fails!
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Pedal cars races (quadricycles) are great events, but HPV championship (all categories), too. I am not sure that there is anything similar here in Swiss. They have down-hill races, but mostly for children and for adults look quite dangerous, so I promised my wife that I shouldn't built one and run down the Alps! Pedal car races are not for me either. No conditions for that, my hart and lungs are of not great capacity and muscles even less. If I am not wrong, some decades ago, in the age of magazines, I found a few articles about pedal car racing in England... They were quite unorthodox constructions, mostly naked... However, there were a lot of interesting and useful solutions, but for me just platonic love in that period. Now, all of them look quite well built with nice aerodynamic bodies. You well described importance of aerodynamic at various speeds. Something like that I was thinking, but without exact figures. For my seeds of 15-20 km/hour in average, some car-body should be helpful but not of great importance? Later I could built simple fabric body over light frame... It seems to me that some of cars have quite tinny wheels, as ordinary bicycles wheels, narrow of big diameter?
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I started to study thread about your Python three-wheeler, with central-steering system... Just covered two first pages. I studied such system a lot, collect a lot of photos and diagrams, but I am not sure if I would consider it now. As I remember, there were systems with steering axle in front of the seat or behind the seat, always with castor angle? In any case, I shall read all of your topic, there are always interesting details that could be useful, or just interesting...
Well, one quadricycle with central steering system: steering axle behind seat, fixed in two steering heads attached to backrest? Front wheel power: no differential, no universal joints: just one jack-axle with pulleys on each of the wheels (slipping in curves and around corners?)… Slipping belts are rude version of speed-changes, too. Naked rims of 16" attached to spokes of two 26" wheels could improve strength and stiffens of big wheels? One big wheel is with 3-gear hub and coaster-brake and another with drum brake - have them on bicycle got from my step-son... Distance of the wheels, smaller, around 10"? Rear wheels of 16", with brakes, wider - around 25". Well, enough for after-midnight thinking/dreaming!
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My English language was improved through decades, and now declining a little. No talking a lot, juts reading and writing, for e-mails and internet forums. Mostly, language of people involved is simplified a lot, some mistakes often happened, slang and abbreviations used a lot (not quite so here in Forum)… Mess in writing as a mess in minds? In elementary school, everybody wanted to learn English: German wasn't popular a lot, French the same. Russian must accept just minority of pupils that must to do that (no good school success before that)… Our father forced us to learn English in spite that his knowledge was modest - learned something in short "partisan course" after 1948 and Yugoslavian brake with the the USSR... He said: learn it well, it is language of the future. So, both my brother and I was excellent in English during elementary school. Unfortunately, in my secondary school (gymnasia as we call it, or grammar school <UK>, or high school <USA>?) - I went backwards having three real bad teachers (professors as they were called) in four years…
However, later I got motive and possibility to improve it. At the end of sixties and early seventies in Belgrade appeared bookstores with foreign, mostly English books and magazines, dedicated to history of motorisation and aviation, railways too - I loved that too). I discovered British Council (English library), American Library too, avoiding Russian Cultural House. However in one Russian magazine I found the first articles about pedal-cars that people there built for ordinary transport, in provinces, small towns and villages... So, I improved my English, mostly in reading, but talking too, during summer holidays at Adriatic Sea Coast (a lot of nice foreign girls were there)… Later, I was working as a lawyer for Belgian-Serbian company and official language on meetings, chatting too, and written correspondence was English language. Nobody of us knew French that Belgians used. I could write letters, memorandums and later contracts and statutes - directly on English - no on Serbian to be translated. I had good colleague, she was excellent in English and I in the law, so we were a good pair... Later came internet and my English became wider, but neither better nor richer...
Good night,
