Critique this performance velomobile idea

[The Toecutter]

No, it doesn't. The statute says it has to have "the ability to be propelled by human power alone." That just means it needs a bike drivetrain that you can pedal if you have to.

Sec. 551.351. DEFINITIONS. In this subchapter:
(1) "Motor-assisted scooter":
(A) means a self-propelled device with:
(i) at least two wheels in contact with the ground during operation;
(ii) a braking system capable of stopping the device under typical operating conditions;
(iii) a gas or electric motor not exceeding 40 cubic centimeters;
(iv) a deck designed to allow a person to stand or sit while operating the device; and
(v) the ability to be propelled by human power alone; and

This means a self-propelled device with qualities (i) through (v). This statute and the statute concerning ebikes is ambiguous, as this bike could fall under both categories if I had a thumb throttle limited to 20 mph. I've heard of cheap 49cc two-stroke Chinese scooters that do not class as a "motor-assisted scooter" because they need to first be pedaled to get going, and thus don't fall under the category of "motor-assisted scooter".

"Highway" in Texas-speak means public road. I'm pretty sure if you kept the right as on a bicycle, you wouldn't have any problems on a 40mph road that allows bicycles. I sincerely doubt you'd be allowed to ride an ebike on "any" highway, specifically high speed limited access interstates where motor assisted scooters would be prohibited.

But do what you want. I suspect it won't be as easy as you think.

I have no plans to use an interstate. State highways seem to be fair game as long as I'm on the shoulder or in the right half of the slow lane.

Of course, the e-bike doesn't quite meet his needs either given that it is limited to 20 mph under its own power. As soon as he exceed 20 mph, his e-bike is no longer legally an e-bike. If he's zipping along at 30 mph and he gets pulled over by a LEO, he shouldn't be surprised if all sorts of bad things happen.

Here's the statute:

(24) "Electric bicycle" means a bicycle that:

(A) is designed to be propelled by an electric motor, exclusively or in combination with the application of human power;

(B) cannot attain a speed of more than 20 miles per hour without the application of human power; and

(C) does not exceed a weight of 100 pounds.


If I set it up as a pure pedelec, human power will be required at all speeds, thus the 20 mph limit would no longer apply.

That being said, none of this is any guarantee I won't be harassed, but legally, I won't technically be violating state law by using this vehicle. I think I will be ok. I've already passed by cops at roughly 30 mph and haven't been pulled over. I don't have a motor in it yet, but had the suspicion arose, they wouldn't have found one.

 

[The Toecutter]

I got some more pics last night with a friend's phone:

Rear view:

Quarter view:

I'm going to source material for a windshield today. The roof piece and turtle deck piece are finished but not yety installed. I'm also going to install the sealing tabs on the mid-section piece so that there are no gaps for the air to penetrate on the sides, reducing drag further.

It's much faster than I thought it would be, but I don't yet have a torque sensor or objective way of measuring power requirements to figure out CdA, Crr, and drivetrain losses. The goal is a CdA of 0.15 m^2 or less. I don't think it's there yet, but it will probably get there.

Note the new rims. The KMX rims kept breaking spokes. On Monday I had a local bikeshop lace some Velocity rims to the proprietary KMX hubs. It brakes much more straight now since hard braking kept destroying spokes on the stock KMX rims resulting in me having to make frequent adjustments.

The wheel discs will go back on the rims after I have them checked out and adjusted by the bike shop next week.

 

[adam333]

Nice

It will probably be very hot to pedal the trike in summer time though.

 

[The Toecutter]

I have a working cooling duct in the front that directs air to my neck. I will also be adding NACA ducts in the mid-section door piece for armpit cooling.

I rode it for about 25 miles today in 77 degree weather with a loaded trunk(50+ lbs of stuff) and it didn't feel that bad. I probably could have covered 100+ miles like this with enough food and water.

This body is still only the 1st prototype. It wasn't anything fancy, but a practical "get 'er done" solution that is reliable and useful. It will serve as a great template for the next design iteration because all of the mounting, ergonomics, clearances, and other practical aspects are already worked out. I can use this thing as a bicycle-car, and fairly reliably, without even having put a motor in it yet.

For the same amount of effort as a light jog, going into a stiff 15+ mph headwind I was able to maintain a 90-100 cadence using the 48T front ring, 21T rear ring on a 26" rear wheel for about 3 miles straight before the road construction necessitated turning onto a side road that had speed bumps. On the way with the wind on a different set of streets, I was able to do roughly 90-100 cadence using 48T/16T for front/rear cogsets.

I bet I could have gone 20+ miles like that in either case. Almost a month ago, I rode 100 miles in a 24-hour period without the midsection piece installed and probably could have gone another 50 before resting for the night.

This thing is awesome. I really badly want the chance to try out a commercial velomobile because it would be undoubtedly greatly more efficient and faster.

I have something envisioned in my head but undrawn that looks like a sort of mix of elements between a Panhard CD Peugeot 66C streamliner, LeMans velomobile, Lotus 119B gravity racer, and an Infiniti Prototype 9 designed in a way to minimize aero drag for the given chosen shape style and practical constraints. I might be able to do a prototype shape in coroplast. I think such a shape on my KMX done right has potential to get a CdA in the 0.09 m^2 range or less. I would need to model it and test it, but we'd be talking about a frontal area around 0.45 m*2 necessitating removal of the steering arms and implementation of rack and pinion steering. This would make it competitive to a Quest, Strada, or Mango velomobile if this were to be achieved, and I know it is possible for an open-wheeled vehicle to get a Cd in the 0.2 range(Rumpler had a 0.28). I think it could be a very aesthetically pleasing, reasonably safe, practical, and not expensive to produce or replicate design when the physical concept is built.

As far as a rack and pinion steering goes, I am thinking of using a butterfly steering wheel(similar to the style in some aircraft) with clearance for my legs/knees, trigger shifters on both sides as well as brake levers, with the right brake lever controlling mechanical discs in the front as well as the trigger shifter for the front chainring, while the left brake lever would control motor regen and left trigger shifter controlling the rear chainring. This would allow me to use the regen as my default brake with my left hand and would be the one commonly shifting gears and the mechanical discs brakes would be used as a panic brake or supplementary brake with my right hand's fingers always in reach and only rarely moved to activate the front derailleur.

 

[1JohnFoster]

In a velomobile you can have shade over most of your body. You can get as much air flow cooling as you want just by opening up the bottom at the front and if you have a kamback, open the back.

Better than, for example, a motorbike stuck in stop & go dressed in black and always fiddling with your visor to keep from baking your head. A bicycle can get pretty roasty too if you get blocked by cars and can't move in the sun.

This thing is awesome.

Congrats, I'm jealous!

~mix of elements between a Panhard CD Peugeot 66C streamliner, LeMans velomobile, Lotus 119B gravity racer, and an Infiniti Prototype 9

Seems that retro-streamlined is your theme in keeping with your Triumph. I always liked the Velayo velomobile, probably not the most aero, but a nice way to way solve the velomobile "knee lump" aesthetic problem with retro aesthetics. Also it looks higher and more visible than a Quest et al.

I always wanted to try to blow coroplast, but like so many things, I'll never get around to. I did do a butterfly steering wheel on my hovercraft when I was 18, and it was cool! Does seem like a more practical way to mount shifters, brake levers & throttle than on a multi-turn round wheel - I didn't ever effectively solve those practical "little details" on my VM.

 

[The Toecutter]

Coroplast is the easiest material I have ever worked with. You don't "blow" it, you cut out the shapes you need and hold them together with punched holes, zip ties, c-clips, loctite, coroplast tab pieces, and gorilla tape. It's stronger than fiberglass in certain measures. It's also flimsy, a trait that deceives with regard to its real strength.

In a few days I will begin riding it back to St. Louis for a total trip length of 1200 miles.

Once back home, I can finish up the GT6 and build a more efficient body shell for this vehicle.

 

[1JohnFoster]

In a few days I will begin riding it back to St. Louis for a total trip length of 1200 miles.

Hope you have a great trip! Good to see you have a bit of time for something other than work... hope you stop to eat, drink and meet some people...

You don't "blow" it

Who says you can't? it'll get stiffer, nicer looking and more aero. Bob Stuart suggested it for future of his "X-4 Cycle Car" https://microship.com/bob-stuart/ - near the bottom.
Holes and zip ties are ugly and unnecessary. I use 3M VHB tape on inside verticies and colour matching tape on the outside. I've made mostly flat folding things; Kayaks, temporary blind and shades for working outdoors, carry cases, and currently a flow measurement hood for ASHP. I only resort to zip ties for kid projects.

It's also flimsy, a trait that deceives with regard to its real strength.

All flimsy sheet materials can be stiffened with gently curved vertices- like the 1/8" plywood VM in my avatar. Coroplast is friken hard to cut in smooth curves. I use long 1/2's as giant compasses with the X-acto blade clamped to the end. Or bent wood guides screwed down.

 

[The Toecutter]

Someone took some videos of it going down the street:

https://vimeo.com/284616898

https://vimeo.com/284616919

The aluminum body I started on is halted due to temporary lack of access to a friends' shop. I'm working on a more streamlined plastic body shell now. The money I set aside for the electric drive system was used to save my mother' house from foreclosure, so until I get that back or can get enough work to sae up the money I need again, I won't be putting the electric motor/battery/controller/other stuff in it.

 

[The Toecutter]

Having spent an entire summer riding this thing and racking up thousands of miles, I can say that it is a bit cooler to operate than a normal bike, as long as I am moving. It gets very hot when stopped at a stop sign or traffic light, but once the air starts to move through the vent, it becomes comfortable. There's been a few times where I've ridden over 100 miles in a day and I did not feel worn out or fatigued.

I've also been more than 50 mph downhill and the trike remained stable even when making lane changes. One has to put in a lot of effort or do something stupid to get it up on two wheels, but I've done such deliberately at lower speeds.

The body is becoming quite worn though and I need to finish up the replacement body and get it on ASAP. A few weeks ago it started wobbling at greater than 40 mph speeds because of creases that have formed in the plastic that have destroyed its former stiffness, and at those speeds, the wobbling is enough to change the trike's trajectory and require steering changes to correct it.

I'm hoping the next body will have significantly reduced drag over this one. As is, the amount of power I can pedal with for hours at a time will allow this to maintain 21-22 mph or so on flat ground, and when going all out with full strength, I can reach about 33-35 mph on flat ground. With the next body, I'm hoping to raise cruising speeds to 25+ mph and top speed to 40+ mph.

I did some coast down testing and came up with an estimate of a CdA of 0.25 m^2. Compared to a commercial velomobile, that's a terrible amount of drag. The Quest velomobile has a 0.08 m^2 CdA for comparison.

There are a lot of sources of drag on my velo that need to be addressed. I have a large vent with an unoptimized air duct in the front for cooling, the mirrors are flat at the front and protrude out of the hood piece, there's no turtledeck, there's a large opening where my head is, there's no boot pieces to seal where the brake lines and suspension stick out from the sides, there's massive foot holes in the bottom of the floor, the trunk lid has 1/4" gaps that are allowing the trunk to act like a massive parachute in the rear, the longitudinal vertices are generating lots of vortices, and the top-down profile does not perfectly track the NACA0026 airfoil I used as a template because I had to elongate the front in order to have enough pedal clearance which in turn makes the entire tail section a massive turbulence generator because it's not shaped properly for the front of the vehicle.

The next shell, it is possible to get the frontal area around 0.5 m^2. I'm using a NACA0020 airfoil as a design template, and unlike the previous design, I'm not distorting the airfoil in any way when looking at it from the top down perspective, so I know the tail is going to be the correct shape for the front. I am going to keep frontal area down by having holes cut into the sides for my steering bars, with spandex boots made. The shell will be exactly the width of the steering bars at its widest point, and the spandex will stretch outward during cornering. There will be a series of small NACA ducts for cooling on this new one, instead of a large vent in the front.

The open wheels are being retained because this configuration is easy to work on and maintain, even though they are terrible with regard to drag. I've had to change a tire and tube 20 miles from home on a sidewalk already and the open wheels made the task extremely simple compared to what it would have been had the body covered the front wheels.

Getting it as efficient as possible with practical constraints in mind is the goal. The next shell should have improved aero, but I know for certain it will have about 30% more storage space and better cooling, as well as a windshield and roof for winter/rain riding. I want to get the CdA of the next iteration to under 0.15 m^2. The possibility of retaining the open wheels and getting as low as a 0.09 m^2 CdA does exist, but getting there without access to a wind tunnel may be difficult.

I'm quite pleased with the results of using a KMX with adam333's front suspension kit. I just need to get the money together to finish it with a drive system. I'm sure the fun factor will increase dramatically with a Leafbike motor and 4 kW to start out with(and the possibility of 5-6 kW with modifications).

 

[adam333]

Thanks for the kind words.

And yes, you will definitively enjoy it even more with a 4kW motor

 

[The Toecutter]

I got the basic pieces of the new body shell mounted last week.

I still need to mount the tail, turtledeck, hood, windscreen, roof, rear wheel cowling, fenders, suspension arm boots, and steering bar side boots, roll bar, among other pieces. With just the middle and front on this trike, the drag is about as good as the entire previous shell I had on it two years ago, and I find that encouraging.

I also have a Leafbike 1500W motor, Sempu 115mm torque sensing bottom bracket, Cycle Analyst v3.1, and other parts in my possession, with a Phaserunner controller on the way. I need to order the battery pack and charger still. I've built up a 26/39/53T crankset with 152mm crankarms and once I install the motor will be running a 34-11T 7sp cassette.

This thing is going to accelerate like a car, be able to reach highway speeds, and theoretically/possibly get 200 miles range at 30 mph and 150 miles range at 40 mph with a rider input of 125W using a 21S4P pack of Panasonic 21700s from a Tesla Model 3, all while staying under 100 lbs.

The law in Texas has changed to include a 750W limit, but I no longer live there anyway.

 

[thundercamel]

I like your parts list The phaserunner, cycle analyst and torque sensing bottom bracket are on my wish list. I haven't quite decided on which one though. You chose Sempu because it's supposed to be the most responsive?

Also I am guessing that the range estimation is optimistic, but we'll see!

 

[The Toecutter]

You chose Sempu because it's supposed to be the most responsive?

I chose it because of spindle width. My current bottom bracket that my Suntour XCT Jr. crankset fits to is 117mm, and 115mm was the closest size I could find for an available torque sensing bottom bracket. 120mm would have been too wide for my front derailleur to work. 115mm just barely works for that.

Even if I get only half that range I'll be pleased. Ultimately, that range will depend on the drag coefficient times frontal area of the vehicle. Frontal area of the completed vehicle is going to be 0.52 m^2 according to a drawing I never got a chance to scan and upload here, but I do not ave access to a wind tunnel and do not know what drag coefficient will be. I'm shooting for a drag coefficient of under 0.3. The wheels are going to have full fenders/skirts over them like the Aptera 2e and the cockpit is going to be fully enclosed with a bubble-top windshield. There will be NACA ducts on the sides plus on the hood piece that will be installed, and a vent behind my head to direct the airflow out at the tail. The tail tapers to a point, but I still need to install that and a bunch of other parts.

Simulation shows me doing 0-30 mph in about 4 seconds. That's basically a car. I already use it like one, with no motor at all. On the way to 40,000 miles for this KMX frame.

 

[adam333]

nice work! :thumb:

It is progressing well.

Those spec seems very good, can't wait to see how it will perform once it is fully assembled.

 

[The Toecutter]

I found a really sweet deal on some A123 ANR26650M1-B LiFePO4 cells, already assembled into 12S4P packs of 36V nominal and 10AH. They were lightly used in a hospital setting and cost only $49.99 each. They include a battery management system that supposedly works. If worst comes to worst, I'll have to take the packs apart and build a pack out of the batteries, but I was planning on doing that anyway out of some much more expensive cells, so if these actually work, I won't need to.

While not my ideal battery, they will get this thing going with an electric assist. IF they work within spec, I'll have a 70-100 mile range at 30-35 mph with rider input being 40% of the motive force. I ordered a cheap $39.99 LiFePO4 charger as well, PWY7205, set up for 24S packs(Output 87.6V, 5A, would basically recharge it in 2 hours from empty).

If this pack works within spec, it will also provide enough power to max out the Phaserunner controller I am waiting on to arrive. Having 7.5 kW peak pushed to my hub motor is going to be all kinds of fun, and I have a torque arm kit for that to keep my frame and dropouts intact.

Should all of this work, I will be much closer to having a practical vehicle that can be used as quickly and efficiently as a car. I also plan to add 50-100W of solar panels with a 72V charge controller, the parts for which have also gotten surprisingly cheap.

 

[The Toecutter]

My batteries arrived today. I need to get a T8 security bit to open the case so I can check the voltage of each cell.

My charger is on the way and should arrive early next week.

I'm still waiting on the Phaserunner controller. Due to the pandemic, the supply line from China has been disrupted. I do not know when it will ship. The seller, Goldenmotor, offered to refund my money but I decided to continue with this order. No one else has these in stock anywhere that I've checked, and my build absolutely needs this specific controller for the efficiency gains it provides, the capability to operate at up to 90V, and more importantly, silent operation of the electric motor.

I still need to finish the tail piece before I can bother installing the motor though. I need to keep that chainline sealed up and wax-dip that new chain before I go through the trouble of installing my new crank and new 7-speed cassette. I want to make this drivetain last for a very long time while requiring minimal maintenance.

I have what is approaching 20,000 miles on my Schwalbe Marathon Plus Tour 26" tire in the rear and approaching 4,000 miles on the two 20" Schwalbe Marathon Greenguards up front, so it will also be time for some new tires soon. I'm going to try to make the current set last until I do the electric conversion, which still might be a month or two away, but the plan is to go with some normal Schwalbe Marathon Plus all around in the interest of reduced cost per mile for tires and longer life span.

I want to do some burnouts with this thing so badly(I still have old tires for that), but I've got to get it working first!

 

[The Toecutter]

The cells are all good. I got the cases mostly apart(I need a 2 inch deep T8 bit to get 3 more screws that were too deep, and cracked the case open), and both read 33.3V. All cell groups(4 parallel) read the same 2.8V. Each pack is 12S4P, 9.2AH.

I will still need to take these packs apart and build a custom enclosure to make them fit underneath the boom. I'm planning on turning these two packs into a 24S4P pack. The BMS it came with is junk, so I will need to install one. My PWY7205 charger has a charge voltage of 87.6V and is meant for LiFePO4, so it won't overcharge the cells.

I will be using a small auxillary battery to run the 12V systems(brake lights, signals, head lights, ect), as well as act as a buffer battery to take input from a 110V AC power supply acting as a DC to DC converter. The aux battery will also have a cigarette lighter inverter plugged into it to run my laptop, charge my phone, and run other electronics.

I'm also budgeting in a 100W set of used solar panels and a cheap 72V charge controller.

I do not know when I will have this running on electricity. Finishing the body is the main concern right now, and that might be a while yet. I do not know when my Phaserunner controller will arrive either.

This new shell is noticeably faster than my previous one. While I don't have photos or a camera, I installed the hood piece and I had no problem reaching 35 mph today, entirely on pedal power, and half the shell is still uninstalled!

 

[1JohnFoster]

This new shell is noticeably faster than my previous one. While I don't have photos or a camera, I installed the hood piece and I had no problem reaching 35 mph today, entirely on pedal power, and half the shell is still uninstalled!

Interesting! It doesn't look significantly different from the photos, apart from the extra chine on top.
Is it longer overall? Did you manage to get the cc area lower? Are you tapering just to a kamback this time?
Do you have a place to do a rolldown test?

 

[The Toecutter]

Interesting! It doesn't look significantly different from the photos, apart from the extra chine on top.

The first shell didn't properly conform to the airfoils I used as templates because the shapes didn't provide clearance for pedaling. I had to elongate the front. This in turn meant that the rear was not shaped properly for the front of the vehicle. Tuft testing revealed that the latter 60% of the vehicle using the first shell was all turbulence. It was still an improvement over the naked trike, but as far as velomobiles go, still quite slow.

This new shell also doesn't scrub over speedbumps and deep potholes, which posed lots of problems using the first shell. It's overall a much more practical design.

Is it longer overall?

Longer by less than 100mm.

The side profile also used a different airfoil as a template. I then transposed them for the cross sections, except instead of having compound curves, the cross sections are 6-sided.

I also designed some wheel covers(full fenders that enclose the wheels) that mount to the suspension blocks, as well as streamlined boots that are going to cover the suspension arms.

It's going to look like a mini-Aptera when finished.

Did you manage to get the cc area lower?

Yes. Right now, frontal area is around 0.5 m^2. Once I add the wheel fenders, suspension arm boots, windsheild/turtledeck/roof, it will be around 0.54 m^2(with new mirror mounts and mirrors, and a few other changes, the potential to get the complete vehicle down to 0.52 m^2 will be there), but with hopefully a greatly reduced Cd, whatever it may be.

Are you tapering just to a kamback this time?

Right now it's a Kammback only because the tail isn't installed. The tail tapers to a point to complete the airfoil shapes I used.

Do you have a place to do a rolldown test?

Yes. The first shell was faster than the naked trike. At only half completion, this new shell is faster than the first shell. Each test was run 3 times and used the same make/model/size of tires at the same pressure during similar weather conditions with the same load.

I have not gotten a chance to tuft test this new shell yet. I suspect most of its drag is from the rotating outboard wheels, which should be altered significantly once the full fenders are over the front wheels.

I'm going to keep tweaking this new shell. I want to get a CdA of under 0.15 m^2. That should allow me to reach my goal of 300W at 30 mph. I will keep tweaking the shape and its pieces to get the CdA as low as possible. It may end up being well below 0.15 m^2. We'll see. The first one was 0.25 m^2, which was kind of crap.

Once I get the aerodynamics the way I want them, I'm going to replicate this shell out of a more permanent material than coroplast, and it will use compound curves to get that extra bit of drag reduction.

 

[The Toecutter]

The tail is now installed. Here's a pic of me riding it while wearing my plague doctor mask(to commemorate The Plague Year. Happy Plague Year everyone!):

It is stable and tracks straight while going downhill at over 50 mph. Still unmotorized. I have a lot left to do to finish the body before I install the EV components(and I'm still waiting on some of the parts, like the Phaserunner controller I ordered months ago), but it keeps getting faster and faster as I add to the bodyshell and reduce drag. Once I get this body shell the way I want it regarding drag, I'm going to build a compound-curved version out of a more durable material than coroplast. The coroplast is just a placeholder. Maybe I'll use fiberglass or carbon fiber.

Once my welding skills are good, I'm going to build a completely custom chassis with 16" motorcycle wheels all around. It will be about the same width as the front suspension equipped KMX, but with a wheelbase about 18" longer and full suspension. I'd like to build an all-wheel drive tadpole velomobile with 3 hubmotors. Unfortunately, all the hubmotors on the market have too much cogging losses for my requirements, as I want it to be operable with the motors turned off while still being easier to pedal at speed than a normal bicycle. But that's a project for the long term future. I have to finish this current one first!

 

[adam333]

great job

Though, it is important to remember that heavier the wheels are, less efficient is the suspension.

 

[The Toecutter]

Indeed. Not just that, but that also means more rotational inertia to overcome, increasing the total energy requirement to build up speed, which can become a major problem when it is being operated under pedal-only mode. I need it to be easier than a normal upright bike to pedal on flat ground, even after everything is installed and it is built up to be a solid and safe performer at highway speeds while using the motor.

This next build on a custom frame may use a custom suspension of my own design. I do not want it to be reliant on KMX steering knuckles.

The entire idea behind this vehicle is that it is off grid worthy, able to be operated as a bicycle without registration/license/insurance, and also something theoretically able to still be operated even in a post apocalyptic world where one cannot find a functioning electric outlet. It needs to be a pedal/electric/solar hybrid that can perform like a sports car when the motor(s) is(are) in use, and even with the drive system disabled, still perform like a velomobile when it is only being pedaled. It must be passable as a pedal operated tricycle to the casual observer and police. Extreme efficiency is thus the goal, but only in the context of everything being robust enough to handle daily use on bad roads at car-like speeds with the motor on, as well as able to handle the abuse of being flogged around a race track. Target total vehicle weight is around 100 lbs, but I'm willing to go a little over if need be.

Thus, I'm looking for the lightest 16" DOT-compliant wheels I can find. I have had difficulty finding the necessary information to aid my search. Few publish the mass of the wheels they have for sale. I like 16" because both moto tires for that size as well as 20" bicycle tires can be used, making them a versatile size, given that bicycle tires of that size are plentiful and currently widely available. A 3T wind Leafbike motor could be laced into one of these 16" motorcycle wheels and set up for triple digit top speeds while still providing good acceleration, plus there are low rolling resistance tires readily available for this size that are also rated for highway speeds(Mitas MC2 rated for 100 km/h) whereas the vast majority of motorcycle/scooter tires have too high of a rolling resistance coefficient to be usable for my application since it still must be operable under pedal-only mode.

 

[The Toecutter]

Today was the first day it ran with the torque sensing bottom bracket(I briefly ran it with a throttle and a loaner controller and cobbled together firehazard of a pack and the bicycle drivetrain removed some months back). I'm using a Sempu with a 115mm spindle width. The CA default specs for this torque sensing BB are wonky and while the rear wheel was jacked into the air it wanted to spin the rear wheel at 50 mph while gently turning the cranks by hand, and the CA was programmed to only turn the motor on with at least 100W pedal input. I adjusted the Nm/V from the default of 50.0 down to 5.0 and that partially solved the issue, but I do not think it is getting an accurate torque/power reading quite yet. But I got it to work at least.

I was sliding around on a snow-filled road at 40+ mph having a lot of fun. This thing is dangerous, even with only 1,250W set up as the power limit using a 46.8V 10.5AH pack of Panasonic NCR18650GA cells, plus whatever my legs can dish out, maybe 1 kW? I'm strong enough to reach 37 mph on flat ground with no motor and the entire body installed, but the tail was removed to make installation of the motor easier and because the tail needs to be modified to accommodate the motor. Once I get my 72V 21AH pack set up and limit it to 4+ kW, I'm going to have to be careful!

The Phaserunner was a pain in the ass to interface with a computer. It refused to work with my Linux machine even though the Phaserunner Suite ran and my USB to TTL cable was recognized and even though I installed all the recommended drivers. I eventually got it to work on a Windows machine after installing some drivers. Then it didn't want to detect the motor because those small Anderson connectors suck, so I went up to O'Reilly Auto Parts and replaced the motor and controller harness's phase connectors with male/female bullet connectors that I crimped to the wire and the motor was finally read and subsequently tuned. The PhaserunnerSuite said my Leafbike 1500W motor's kV was 11.6.

I have the following tasks to do before this thing can be used on a reliable basis as an EV:

*Make permanent mounting locations for the Cycle Analyst, Phaserunner, and battery pack. The CA and battery pack are held to the boom with zip ties at the moment. The Phaserunner is hanging out loose unmounted to anything.
*Install a kill switch. My only on/off switch is the XT60 connector on the back of the Phaserunner. The Andersons connecting the battery pack to the controller have also got to go because they shut off intermittently due to bad contacts and vibration.
*Take off the Andersons for the battery pack and replace the GND wire with male/female bullet connectors and route the positive wire to the kill switch, terminated with ring connectors
*Put the tail section back on. I need the trunk space to carry my tools and spares so that I don't ever get left stranded

There are a lot more tasks required to finish it, but the above will make it suitable to live on a daily basis with while I keep working on it.

Once I get it into something I can use on a daily basis and ride it around a bit to figure out its performance parameters, I'm going to get some pics and make a new topic showing off the build. I suspect with this battery and given the motor's observed kV rating it will do about 45 mph on flat ground on a freshly charged pack, 42 mph towards the end of its discharge curve. Which would mean the 72V pack could be good for 65 mph!

 

[neptronix]

Very cool bike so far.. subscribed!!

 

[The Toecutter]

I'm thinking about how I'm going to eventually style this thing.

Three possibilities in mind:

1) Black with a big red anarchy sign sloppily spraypainted on the side. I could call it "Chaos".

2) Silver and black with a 3D printed Baphomet hood ornament, with pentagram decals on the front wheels. I could call it "Satan Bike" and put in a sound system so I can ride around in it playing black metal.

3) Faux wood grain with gold-colored ornamentals, cast wheels made to resemble 19th century style wagon wheels, grim reaper or a silver skull 3D printed hood ornament, with a red velvet button-lined seat. "The Rolling Coffin".

I'm so glad I put this together. I knew it was going to be a fun bike, but I really had no idea... Now I need to work on making it safe/reliable to use, before working on the aesthetics.