Turning a state of the art Velomobile into an ultra efficient electric enclosed 70 MPH 150 mile range motorbike

[marcocolo]

The title pretty much says it all. I've been thinking about wanting to create an ultra efficient electric vehicle for years. I'm been into motorbikes for many years and have a 35mph ebike that I enjoy. I love the prospect of the Aptera 3 wheeler but wonder if it will ever get to market.... What I want to create is a "proof of concept" that you can make an electric vehicle that can blow away efficiencies- that truly is the kind of thing that is somewhat practical and totally functional.
I have a Tesla. It does many things right but so many wrong. It's too heavy, not aero enough. So I have decided to blow some $ to create a 3 wheeled, enclosed, lightweight, ultra aero "motorcycle".
My design goals are:
1) Keep it as light as possible but still roadworthy at 70. (power, brakes, suspension)
2) Make it practical to use daily- would need to be able to go in reverse and have regen braking on the rear hub motor.
3) Be able to go at least 150 miles in real world usage on a charge.
I figure this should be able to be done given the aero nature of the DFXL velomobile body I'm planning on using for the body. It seems no one has really tried this before. I figure based on low weight and aero, I should be able to get by with a lower output motor and a smaller battery pack. Probably need 72V setup. I plan on moving the front wheels out from the body for stability, making them smaller for aero and using disc brakes front. Want the suspension to be as simple and light as practical. Frame out of lightweight aluminum.
Once I remove the guts of the DF it should weigh about 25 lbs. It has its own 12V system to run the lights, turn signals , etc.
I'm looking for help with someone to design the propulsion aspect (motor, controller, batteries needed, display and controls) and someone to design and build the chassis -frame to hold me and the batteries, swingarm, front suspension, steering and brakes, etc.

Anyone have any thoughts, names of people? Tell me I'm crazy? Thanks for listening to my dream.

 

[gromike]

Off hand I'd say a rear Grin all-Axle direct drive motor, and a V6 Phaserunner controller would be a good way to go.
My All-Axle motor does 43mph unloaded at 52v, 35mph on throttle only on level ground.
A lot of people use direct drive motors from Leaf Bike.

 

[OlderGiantFan]

Very cool marcocolo, I love that velo, I took a copy for a desktop pic I can't believe how cheap they are, many pushbikes are that price and higher. Good luck with the project, keep us updated hey. @Toecutter may have some advice for you, he's the resident velo expert, at least in my opinion.

I hate AI, but the google one say this

AI Overview

"Toecutter" is an active, experienced user on the Endless Sphere DIY EV Forum, known for high-power electric vehicle builds, particularly KMX-based electric trikes and velomobiles. They frequently contribute insights on performance, stability, and DIY e-bike components like torque sensors.

Sorry Toecutter, but you're famous now

 

[marcocolo]

Off hand I'd say a rear Grin all-Axle direct drive motor, and a V6 Phaserunner controller would be a good way to go.
My All-Axle motor does 43mph unloaded at 52v, 35mph on throttle only on level ground.
A lot of people use direct drive motors from Leaf Bike.

While the Grin is a great motor, I don't think it's powerful enough for this project. Remember 70 mph top speed and no pedals, chain or gears. Pure motor power. I'm thinking I'll need closer to 6000 watts back there?

 

[bananu7]

First off, sweet project. I'd love to build something along those lines one day.

You have a really good and lightweight base, and ironically, that's your first issue. You cite 70 (112km/h) as desired top speed. First off, you'll need tyres rated for at least 120km/h. The Durano Plus E (if I'm squinting correctly) is rated to just 50km/h. Narrowest tyres meeting this rating I could quickly find land you at 2.75" x 17". That's about 70mm wide and would require completely different rims. Maybe you can find something even skinnier than that, but then you're likely getting into specialized products for stuff like speed records etc. that will be hard and expensive to buy and most likely won't have any street legal paperwork.

Then, the fact that it's so light is starting to play at its disadvantage. At speed, weight is your friend, as it adds stability. Even with such an aero shell, a strong gust at 100+km/h will send you flying sideways or at the very least cause hard to control steering inputs.

150 mile range is actually very doable even with a quite small battery (say around 2kWh), as long as you don't plan to cruise at such high speeds. Again, even with excellent aero, you're going to quickly run into significant wind resistance which will eat into your efficiency.

Personally I think I'd relax the max speed requirement down to 40-50 mph range, and work from there.

P.S. the motor power is going to be the least of your problems, as long as that frame can take some big hub. If you're limited to regular QR motors, though, that might become an issue at cruise - but again, only at high speeds. My recommendation would be to start with something you can fit more easily like a 3K-turbo, Grin or equivalent, which should peak at 6kW to give you a sense of possible acceleration and speed, but quite likely won't stay cool enough for cruise at those power levels, and move to a larger motor only once you confirm the chassis, tyres brakes etc. are up to speed. You can get the full desired size controller and especially battery from day 1 though.

 

[Apartunis]

Is that velomobile a structural monocoque? I can not find out by looking it up. Whether it is or is not, the body will probably have to get beefed up significantly to tolerate the added gross weight along with dynamic forces plus shocks and vibrations.

You are talking about going for a sailplane level of efficiency, without the sailplane's advantage of only getting beat on by air when at speed. I think it would be feasible to make it work on a prepared test track, but it can not be very much like a sailplane while coping with typical surfaces and traffic situations at the speeds you suggest.

High speed HPVs can only be as light and efficient as they already are because they do not go very fast very often or in ordinary traffic.

 

[ZeroEm]

The title pretty much says it all. I've been thinking about wanting to create an ultra efficient electric vehicle for years. I'm been into motorbikes for many years and have a 35mph ebike that I enjoy. I love the prospect of the Aptera 3 wheeler but wonder if it will ever get to market.... What I want to create is a "proof of concept" that you can make an electric vehicle that can blow away efficiencies- that truly is the kind of thing that is somewhat practical and totally functional.
I have a Tesla. It does many things right but so many wrong. It's too heavy, not aero enough. So I have decided to blow some $ to create a 3 wheeled, enclosed, lightweight, ultra aero "motorcycle".
My design goals are:
1) Keep it as light as possible but still roadworthy at 70. (power, brakes, suspension)
2) Make it practical to use daily- would need to be able to go in reverse and have regen braking on the rear hub motor.
3) Be able to go at least 150 miles in real world usage on a charge.
I figure this should be able to be done given the aero nature of the DFXL velomobile body I'm planning on using for the body. It seems no one has really tried this before. I figure based on low weight and aero, I should be able to get by with a lower output motor and a smaller battery pack. Probably need 72V setup. I plan on moving the front wheels out from the body for stability, making them smaller for aero and using disc brakes front. Want the suspension to be as simple and light as practical. Frame out of lightweight aluminum.
Once I remove the guts of the DF it should weigh about 25 lbs. It has its own 12V system to run the lights, turn signals , etc.
I'm looking for help with someone to design the propulsion aspect (motor, controller, batteries needed, display and controls) and someone to design and build the chassis -frame to hold me and the batteries, swingarm, front suspension, steering and brakes, etc.

Anyone have any thoughts, names of people? Tell me I'm crazy? Thanks for listening to my dream.

First, your not crazy. Second i'm with bananu7.
Don't want to discourage you. Just remind you of safety, which means motorcycle parts and DOT tires. Maybe a roll bar or cage.
If not lower speeds.

 

[marcocolo]

I was definitely planning on motorcycle (or scooter) tires. The velo is monocoque but I'm using it as an aero shell, it won't take any stresses other than wind and bumping down the road. I'm hoping for the whole thing to weight about 150 (mostly batteries and the rear hub). I will set the velo on top of the frame or inset the frame into the shell (cutting out parts of the bottom).
I'm not looking for it to be able to corner at 50 but be super efficient, not a hot rod....

 

[AnthonyC]

Bananu7 nails it, speed's the issue. With the DF originally having a single sided swingarm and elastomer front suspension there's a lot for the alu chassis to do so it won't be light. Practical daily means it has to protect you too, more weight. Ultra low CdA is hard to maintain, outboard wheels and cooling 12% of 6kW would affect it a lot.

Somewhere there'll be a crossover where enclosing a motorcycle's a better starting point. If you aim for a speed that's "fast for a DF" refinement could work instead of wholesale replacement, and there's more chance of keeping the great feel of riding a second skin.

There's a central european company who were well known for velomobiles who've recently relocated their premises to focus on an e-VM product. They may have been at the last SPEZI (International Special Bikes Show), sorry I don't recall the name.

Edit: (Other posts overtook my typing) I think travelling over 40mph while unable to corner at 50 is a lousy idea.

 

[Apartunis]

I will set the velo on top of the frame or inset the frame into the shell (cutting out parts of the bottom).

The first approach would adversely affect aerodynamic qualities, the second could take away the body's structural integrity. Maybe an internal frame with a minimum number and size of holes through the body for necessary components. I think it is a good idea to use a structural monocoque as an aero shell because aerodynamic forces will be so much higher than the donor vehicle anticipated.

 

[marcocolo]

Bananu7 nails it, speed's the issue. With the DF originally having a single sided swingarm and elastomer front suspension there's a lot for the alu chassis to do so it won't be light. Practical daily means it has to protect you too, more weight. Ultra low CdA is hard to maintain, outboard wheels and cooling 12% of 6kW would affect it a lot.

Somewhere there'll be a crossover where enclosing a motorcycle's a better starting point. If you aim for a speed that's "fast for a DF" refinement could work instead of wholesale replacement, and there's more chance of keeping the great feel of riding a second skin.

There's a central european company who were well known for velomobiles who've recently relocated their premises to focus on an e-VM product. They may have been at the last SPEZI (International Special Bikes Show), sorry I don't recall the name.

Edit: (Other posts overtook my typing) I think travelling over 40mph while unable to corner at 50 is a lousy idea.

I meant I don't need it to handle like a sports car around corners....

 

[marcocolo]

The first approach would adversely affect aerodynamic qualities, the second could take away the body's structural integrity. Maybe an internal frame with a minimum number and size of holes through the body for necessary components. I think it is a good idea to use a structural monocoque as an aero shell because aerodynamic forces will be so much higher than the donor vehicle anticipated.

You may be right. I wish I could speak to someone who is a really good fabricator. I'm quite handy and have made a lot of stuff in my day but aluminum welding and figuring out suspension front and rear is beyond my capabilities. Also figuring out the proper hub to use, how much and which batteries and how and where to mount them, and designing the front suspension and steering.....

 

[bananu7]

I was definitely planning on motorcycle (or scooter) tires.

Good, but then the next (logical) step is wheels. Skinny moped tyres would work very well, and I'd personally likely go for spoked wheels with aero disc covers on top. However, you need single sided narrow hubs compatible with that. Those do exist, but might be tricky to find one that'll fit everything else. Thankfully in modern days, a custom-machined set wouldn't be prohibitively expensive. Alternatively modifying a cheaper hub with a set of bearings able to support single-sided mount loads could be a cheaper option. So I'd say that's your first homework - if you want to run motorcycle tyres, establish the desired size and find out how are you going to build your wheels.

figuring out suspension front and rear is beyond my capabilities. Also figuring out the proper hub to use, how much and which batteries and how and where to mount them, and designing the front suspension and steering

This sounds a bit problematic, though. You can't really buy the engineering time required here. I mean, you could, but anyone that's good enough to even have a quote would be prohibitively expensive. Engineering a whole chassis from scratch for yourself requires dedication, patience, optionally a CAD software and some welding skills. Engineering a chassis for a client means you become responsible for someone else's life, and I expect $50k to be absolute minimum starting point if done professionally.

So, not to sound discouraging, I see three reasonable options here:
1) you get a teammate/partner that can fill the gaps in the skillset and will work for free, likely building two vehicles at once
2) you open up youtube and start filling your head with as much knowledge and practice as you can, aiming for something doable that you can design and build, not necessarily perfect or optimal in terms of performance
3) you copy an existing design (buying plans is also an option)

P.S. And i know I'm repeating myself but the drivetrain part of it (battery + hub + controller) is by far the easiest part of this endeavor. Mainly because it's been done so many times, that you can fall back on previous experience and tons of forum posts, while chassis geometry for such vehicles is reserved for few select individuals like Toecutter. You really should read his threads start to finish.

 

[SlowCo]

Alternative idea is to use the front end of a small ATV/Quad/Buggy type vehicle with the suspension, brakes and steering and weld a steel tube chassis to connect a rear swing arm of a moped/light motorcycle fitted with a hub motor wheel. Then build your own body over it.

 

[ZeroEm]

Toecutter added front suspension that moved his front wheels out, this added stability. I'm a trike guy. wider front will stop you from riding some trails and no going thru door ways.

Don't give up you may need to do some research on different built trikes and find something close to what you want and go from there. Refer to SlowCo post.

Something like this.