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Reverse thinking...

Desertprep

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I have read many threads here and in other forums about people trying to convert a car that originally had an ice into an electric vehicle. Has anyone tried to design a vehicle from the ground up to be an electric vehicle? I am looking for ideas and threads that can be accomplised by mortal man - not requiring $billions. What I hope to find is a 2 seater, 3 wheeled (tadpole) that has a lot of storage in the rear - a 3 wheeled pickup, if you will. Bonus points awarded if it has all wheel drive, even if the 3 wheel is only used at low speed. Must have a safe cruising speed of 60 mph. Maybe...by the time these requirements are satisfied, it would have been cheaper to convert a small 4x4 jeep? or an older awd Subaru?
 
You can do a lot with a good tadpole trike with a fairing. But you're not going to (safely) get to 60mph. That's more work than you will want to put into it, unless you're a mechanical engineer with a long, long history of design.
 
whatr you are nearly describing is a Jitney, I have seen electric ones on various chinese sites. I don't know about that top end though. Most small track vehicles have issues over something like 45.. I would love to explain it but I have no idea why it is a thing. I only know that much because of getting a custom built (ICE, not electric) car road verified.
 
As others have said, highway speeds and 3 wheelers (or highway speeds and homemade vehicles) are a bad combination almost all the time. If you want car speeds, start with a car (and feel bad about it, as you should).

Why would you want to put the load bed over a single wheel? For a 3 wheeled, 2 seat truck, there's already a proven format: Piaggio Ape, Cushman carts and all the parking enforcement trikes, maintenance trucklets, and south Asian tuktuks that descended from those.

800px-Bee_transports_wasp_in_profile.JPG


If you use delta or 4-wheel layout, you can put the rear wheels on trailing links for a low cargo floor, sub-floor battery, or both. With a single rear wheel you lose all of that and you twist the bejeebers out of the swingarm when the contraption is loaded.

Tadpole layout is for when the weight is mostly on the front. Delta layout is for when it's mostly on the back.

For 3 wheeler speeds, it's a no brainer to use hub motors, in which case all-wheel drive is easy (and doesn't have to interfere with a low rear floor).
 
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I had spaced the name for the Euro-version of the lil trucks. I just got used to seeing Jitneys allllll over S.E.A. The amazing thing is in parts of India the guys in the peddle units are keeping up with the gas powered ones.. After seeing the traffic there however I think it is a survival thing.
 
I have read many threads here and in other forums about people trying to convert a car that originally had an ice into an electric vehicle. Has anyone tried to design a vehicle from the ground up to be an electric vehicle? I am looking for ideas and threads that can be accomplised by mortal man - not requiring $billions. What I hope to find is a 2 seater, 3 wheeled (tadpole) that has a lot of storage in the rear - a 3 wheeled pickup, if you will. Bonus points awarded if it has all wheel drive, even if the 3 wheel is only used at low speed. Must have a safe cruising speed of 60 mph. Maybe...by the time these requirements are satisfied, it would have been cheaper to convert a small 4x4 jeep? or an older awd Subaru?

Not sure if you've ever looked around the roads, but there are plenty of EVs that were designed *as* EVs, sold commercially, so there have most definitely been some. If none of them fit your specific needs or conditions, you could probably at least take info, parts, design ideas, etc. from them.

There is a website I can't recall the name of that is a "library" of assorted EV builds; most are conversions but there have been some scratch builds on there.

DIY Electric Car Forums may have some, most of the ones on the above site were probably started on this one.


The actual primary vehicle design will not depend on power source, but instead will depend on your specific usage, conditions, etc, so you would not want to restrict your research to EVs.


For three wheelers...others have pointed out various disadvantages of them, but it depends on your specific design and intent, so you'll have to look at the reasons for the disadvantages, compare them to your specific list of needs and functionality requirements, and see if they apply to your design ideas. If all you need is totally straight line high speeds it's not such a big deal, but if you need to maneuver at those speeds, your design is going to have to be built like any other similar threewheeler that can safely do whatever you need it to do, or you'll have to come up with a new design that does.



The big problem with something that's a three wheeler truck is it's going to almsot certainly have to have two wheels in the rear to handle the load. That makes it MUCH less maneuverable at higher speeds, cornering, etc., as it is much easier to roll over or flip.

My SB Cruiser trike is a tadpole "pickup", and at the 20mph max it's designed for, it does alright, but even if it had suspension of the right design, it still wouldn't be able to make safe full-speed turns. (unless it had specific anti-roll features, it would actually be LESS safe with suspension). I have to slow down at least a few MPH for wide left turns, and sharp right turns take me down to less than 3/4 full speed, usually less than half. Certain maneuvers even in straightline riding are not safe at full speed. And this is with relatively heavy hubmotors on the outboard edges at the rear, and all the load low down. If the load fills the back end, or requires the top cargo deck as well, it becomes much less maneuverable at higher speeds. Etc.

If I were using motors not at the wheels, but further inboard, or centralized, etc., there would be less "ballast" holding the wheels down, and it would be even more tippy in turns. There are ways to compensate for all sorts of maneuvering challenges, but everything gets more and more complex, which gives more and more points of failure, more maintenance, etc.


So, you should to look at how the things that already do what you want work, regardless of power source, and see how they do what they do. I recommend finding some you can test drive to see what they actually perform like in your specific conditions and usage.

If no vehicle like you want exists, regardless of power source, you're going to have to research how to design one that does, build it, and redesign it in iterations until it does what you want. ;)

That's what my SB Cruiser project has been.
 
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What I hope to find is a 2 seater, 3 wheeled (tadpole) that has a lot of storage in the rear - a 3 wheeled pickup, if you will.

I found a beast that (almost) matches your criteria - Maybe they're willing to offer an optional trailer hitch?
 

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The big problem with something that's a three wheeler truck is it's going to almsot certainly have to have two wheels in the rear to handle the load. That makes it MUCH less maneuverable at higher speeds, cornering, etc., as it is much easier to roll over or flip.

There's nothing inherently worse about delta trikes than tadpole trikes when it comes to cornering ability. It's only a matter of how wide the track is, how low the center of mass is, and how close it is to the midpoint of the paired wheels.

That's why delta layout with a low floor load bed is best, for any vehicle in which the cargo can substantially outweigh the passengers. You put the heavy stuff as low as you can and as close to the center of the "axle" as you can.
 
There's nothing inherently worse about delta trikes than tadpole trikes when it comes to cornering ability. It's only a matter of how wide the track is, how low the center of mass is, and how close it is to the midpoint of the paired wheels.
Touché Big Guy.... you took the words right off my keyboard (y)
 
I see the guys on the reverse trike bikes (there is a group of them that roar around the delta on weekends those seem pretty stable... but I am fairly certain that if you have an 80ish k budget you can probably afford more suspension than the average e-bike has. (someone told me that the top end of them monsters breaks 120k for a price tag, I will stick with a lovely german car tyvm)

I would totally steal their suspension if I thought I could figure out a way to peddle it at 50mph....
 
I have read many threads here and in other forums about people trying to convert a car that originally had an ice into an electric vehicle. Has anyone tried to design a vehicle from the ground up to be an electric vehicle? I am looking for ideas and threads that can be accomplised by mortal man - not requiring $billions. What I hope to find is a 2 seater, 3 wheeled (tadpole) that has a lot of storage in the rear - a 3 wheeled pickup, if you will. Bonus points awarded if it has all wheel drive, even if the 3 wheel is only used at low speed. Must have a safe cruising speed of 60 mph. Maybe...by the time these requirements are satisfied, it would have been cheaper to convert a small 4x4 jeep? or an older awd Subaru?
Yes, there are several companies and individuals designing electric vehicles from the ground up, often with unique configurations like the one you describe. Check out Aptera's 3-wheeled solar EV, Electrameccanica's Solo, and open-source projects like the Tabby EV. Converting existing vehicles is also viable, but purpose-built EVs can optimize factors like aerodynamics and weight distribution. A well-executed ground-up design could potentially be more cost-effective long-term, though converting a used vehicle may be cheaper upfront.
 
There's nothing inherently worse about delta trikes than tadpole trikes when it comes to cornering ability. It's only a matter of how wide the track is, how low the center of mass is, and how close it is to the midpoint of the paired wheels.
Touché Big Guy.... you took the words right off my keyboard (y)

Maybe 'inherently' - but it seems like 'real world', turning is most often associated with a braking/deceleration event. Certainly so in most any sort of 'panic event' as in 'hit the brakes and swerve'. In all those deceleration/turning cases, the 'delta' throws the resultant force vector out over empty space where the 'tadpole' throws it out to a load bearing front wheel.

For 3 wheels + cargo, sounds like you want a Reliant Robin
 
3-wheelers are inherently unstable. If high performance is your goal then it is a lot better to go 4 wheels. There are potential benefits to 3 wheelers, but handling performance isn't one of them. This is why, historically, people used three wheelers for reasons unrelated to performance... like taking advantage of taxes or reduced regulations relating to motorcycles so they can make things cheaper.

The instability can be overcome somewhat through proper engineering and there are so many aspects and compromises to do with things like roll center vs center of gravity versus track width vs suspension design vs inertia and all that stuff that is impossible to go over all of it.

Whether delta vs tadpole setups the choice comes down to different sets of compromises.

For example: On delta design if you are doing hard braking while turning you are more likely to tip over. For tadpole if you are doing hard acceleration while turning you are more likely to tip over.

And this actually happens. A typical tadpole tip over situation is were a person is turning in front of traffic and misjudges how close or how fast the opposing traffic is. So they try to accelerate out of the way, the car goes flying out from under them as they flop over, right before getting hit by the car going the opposite direction.

And if you put the weight forward on a tadpole to prevent it from tipping backwards under a hard turn then under hard braking it will tend to want to just flip over forward and do a endo.

Just like modern cars the delta design tends to understeer and plow through corners. In 4 wheelers understeer is built into the suspension by design because it is much more predictable and the average driver reacts much better to understeer.

Ultimately all you need to do is go and look at the situations people use one design over the other. And it is pretty consistent... Delta 3-wheelers are work horses. They carry heavy loads and are used for people movers the world over.

Tadpole trikes work better if the weight is extremely low-slung for a sporty setup. But they need to be suprisingly wide to be stable around the corners.

Going with a delta design is a no-brainer if your goal is to haul things.
 
3-wheelers are inherently unstable.

False. I'll keep saying it as long as people keep spouting nonsense about it: it's all about the weight distribution and track width. 3 wheels can be done right, and 4 wheels can just as easily be done wrong.

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If high performance is your goal then it is a lot better to go 4 wheels.

Only if you're willing to "spring" for 4 wheel suspension. A three legged stool doesn't require a flat floor, but a four legged stool does. So I argue that if you aren't using suspension, three wheels beats four every time.
 
Must have a safe cruising speed of 60 mph

You may choose this for your own reasons, but I suggest an alternative.

There are many good reasons to design our towns and cities so that walking and other short travel suffices. For use in the distorted cities we have (and between them) high speeds may be useful, but living this way guarantees high resource consumption and that's not wise for the long term.

I think it would be better for a society to make it more obvious to the participants what the cost of their lifestyle is to avoid overwhelming the ecosystem. We just don't actually need so much - we just are willing to trade short-term personal thrills for responsibility.

Unfortunately, this also empowers idiots to try ridiculous schemes, including political ones. If I leave food lying around, something (or some idiot) will try to eat it. Better to have less extra available.
 
... Maybe...by the time these requirements are satisfied, it would have been cheaper to convert a small 4x4 Jeep? or an older awd Subaru?
Agree ... it's enuf of a labor intensive reverse challenge (and expense) just converting one of the above chassis ... than starting from the ground up. Why "Reverse Thinking..." a platform chassis when there are already available options for any tweaking.

You may conclude that it makes just as much sense (or more) to stay with a rebuilt ICE than conversion to a LFP electric power plant.
 
Wow! Lots of good info out there....you have convinced me...I am now looking at 4 wheel alternatives to use commuting around town and between towns. Most towns where I live have no more than 5K people and are strung along a county road or a highway, usually 3-7 miles apart. I will get back to you when I have a semi-turnkey system.
 
Why would you want to put the load bed over a single wheel?
Because the time you really care about handling and stability is during an emergency stop. And at that time, two wheels forward gives you the most stability and resistance to rolling.

For low speeds a design like this works well.

 
Desertprep,

You might want to look for a second hand Arcimoto. It's an Electric Tadpole. They are well built and 80 MPH capable. They made some very cool delivery vehicles as well as their basic two seater. The company was just delisted from NASDAQ and their website seems to have been shut down. The vehicle got good reviews but they never sold enough to bring the price down to a competitive level. Here is a pick-up conversion.

arcimoto pick up.jpg

Their 'Last Mile' delivery vehicle was slick too:

arcimoto delivery.jpg
 
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