Tilting Tadpole. how does the front mechanical assembly work?

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Anyone ever make a tilting tadpole trike like above video? The front shopping basket blocks me from seeing how the tilting work. Does anyone know of any plans showing how to make one?
 
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There's quite a number of ways of achieving this. This one balances just like any bike:-


and here's one I made earlier:-



This one uses the same system as mine:-

 
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like this I assume ?







not hard to find if you look for Kiffy tilter in Google images ?
 
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I like this one, they used to sell the trike on their website. all cnc cut aluminum plate and welded together. and packs up to half its' size.
Unless I'm mistaken that one isn't really a leaner. It will lean to some degree due to suspension give but that suspension is largely there as suspension. The way it stands on it's own shows the suspension is forcing it to do that. You can make a true leaner stand up on it's own as per mine via a brake disc that operates in the direction of lean but I see no similar system here. I would expect it to lean outwards in any bend in proportion to the forces applied and the give in the suspension just like a car without an anti-roll bar. The suspension is working against any attempt by the rider to lean it like a bike.

The kiffy is about as simple a system as it's possible to use. A pair of arms each pivoted so that any central lean is replicated at each end. No suspension and must be balanced like any bike. The top one I linked above is the same basic principle but with suspension. The suspension works on one arm against the other so still leans perfectly (if you lean it over the spring doesn't compress) whereas the aluminium trike's suspension operates against the main frame and thus stops any leaning. If you tried to push it over the inside suspension would resist it.
 
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I found these better photos on ebay. the wheel is just soem laser cut 1/8" steel bent into a channel.
looks like some bearings on the 2 rotation points by each wheel.
I wish I could see the center 2 rotation points better. What kind of bearings would one suggest for the center? Sorry for the newbie questions. I've never seen or studied suspension before.
 
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The suspension units are very interesting in that it appears to be two units rather than one. Other pictures show zero suspension units! One unit would intimate that it was like the first one I posted in this thread but two intimates that the central mounts for each are against the chassis which would work to prevent lean. The springs are exceptionally weak and as such simply can't do the job of suspending or do much of a job in preventing lean. They may be there to try to damp down some instability in the system much like a steering damper "cures" faults.

Whatever bushings are used at the end can be used centrally too. I'd expect them to be fairly simple bushings. You'd not want anything like a rubber bushing as any give will make the thing hiddeous to ride. Only bearings with no give would be any use. Perhaps a pair of split flanged PTFE bearings would suffice. Note that the upper arm is actually two arms with two pivots centrally whilst the lower arm is all one unit and goes from one wheel to the other with one central pivot (this guarantees it can't use actual suspension). This is to get the wheels to camber into the turn slightly. I'm unsure why anyone would want to do that since it leans as per a bike and therefore the wheels lean too. Getting wheels to camber into a turn is useful on a non-leaning vehicle but not this. Eg. a car would have unequal length wishbones to alter camber as it compresses to make the outside tyre dig in rather than try to roll itself off the wheel. If copying this I'd start off with both arms being one unit each with one central pivot each.
 
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"Note that the upper arm is actually two arms with two pivots centrally whilst the lower arm is all one unit and goes from one wheel to the other with one central pivot (this guarantees it can't use actual suspension). This is to get the wheels to camber into the turn slightly "

Thanks I wondered how that top arm could lean with 2 bolts in it, now i understand how it works. I think the springs are in there to keep the bike upright. Otherwise it could just flop over and tilt to one side.
 
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Yes - I think you are correct in that those weak suspension units are little more than keeping it upright when left. Perhaps the one with suspension units is a prototype and the one without is not, or visa-versa, or perhaps they are an option.
 
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I wrote all 3 usa distributors last week and the main company in France. Zero email responses today I would think with such a niche product they would have a fast response. This bike is $2500 to $4800. edited to add a week later and no response, pretty amazing they sell anything.
 
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