Leaf / leafmotor / leafbike high efficiency 1500w motor

Hickbeard said:
I actually think that cyclists should have to have public liability insurance.

You reckon? How about pedestrians? Some are more dangerous than others.
 
Insurance...what a scam. It's betting that something bad will happen to you and then allows everyone involved to not take responsibility for their actions. On top of support of companies that have a financial interest in not paying what they agreed to pay (or what the customer thought they agreed to pay), the insurance system helps give financial support to lawyers.

When the greatest harms on this planet are done to the general population or big segments of the population by big entities who aren't required to pay for those harms or carry insurance to pay for them, but the government is preoccupied with whether or not a ebikers have insurance on their vehicles, something is seriously wrong.
 
John in CR said:
Insurance...what a scam. It's betting that something bad will happen to you and then allows everyone involved to not take responsibility for their actions. On top of support of companies that have a financial interest in not paying what they agreed to pay (or what the customer thought they agreed to pay), the insurance system helps give financial support to lawyers.

When the greatest harms on this planet are done to the general population or big segments of the population by big entities who aren't required to pay for those harms or carry insurance to pay for them, but the government is preoccupied with whether or not a ebikers have insurance on their vehicles, something is seriously wrong.

Well, when people insist on driving cars and doing other things that constitute a public menace, you have to offset the harms somehow. I think we need mandatory gun insurance, for what it’s worth. Let those who impose the risks pay for the consequences.

A 200 pound guy on a 200 pound bike moving at 100 mph packs slightly more kinetic energy than the same 200 pound guy in a 3000 pound car moving at 35 mph. And a car hitting something at 35 mph can really mess it up.

That’s one of your bragging points, right? 100 mph? But you don’t think it’s right that we should require liability insurance of you.

Electric bicycles aren’t required to carry insurance, and they are only allowed to go bicycle speed. At least in places that have done any serious thinking about it.
 
Balmorhea said:
Hickbeard said:
I actually think that cyclists should have to have public liability insurance.

You reckon? How about pedestrians? Some are more dangerous than others.
Yeah. I mean all other ROAD users are required. Cycles use the road, well at least in the UK. So why are they special.

And honestly most cyclists that I know or come into contact with are arrogant dicks who think they have more rights on the road than anyone else.

Think it's only fair.

I used to have £10million public liability for PT. Only cost like £60 a year.

Sent from my CLT-L09 using Tapatalk

 
The US system seems fair to me. E-bikes that are within specified limits don't need insurance or license. Those limits, basically 20 mph on bike paths (I know it's possible to go much faster on a pedal bike) and 28 mph in bike lanes contiguous with roads, are reasonable. Insurance is a curse the rest of us need to live with or we can move to another country. I'll stay!
 
My Insurance 12 years ago was $22. Moved to San Antonio, TX where I live now. It went up $40, $60, jumped to $120 changed companies to keep it at $60 for a few years, then went to $120. Got so tired of it, sold my truck bought an electric car and share it will my mother who supplies the insurance. Was $150 month down to $135 at the moment.

My mother claims it's her age but i'm with John in CR it's a scam. you think it's me, have not had a speeding ticket, wreck or pulled over for anything in 27 years. Have my licence with no issues. Me and my mother together only put 2000 miles on the car (Insurance $1800) last year, put same miles on my E-trike last year. Lets do the math that's 1800/2000 = $0.90 a mile. I can hire a taxi for that, told my mother when she does not want to pay it anymore then sell the car.

That is how I came to ES to build a car replacement but not a car. My trike is first attempt with the leafmotor.

Thinking want a smoother ride, cargo room or good trailer, Maintain 35 mph/56 kph no faster. AWD trike, leafmotor in the back, two grin's front motors in the front, need a good frame and lots of battery.
 
What are the standard connectors on the leaf motor controller?

I cut them to fit into a single connector and that was a mistake.

Can't find which ones they are?

Sent from my CLT-L09 using Tapatalk

 
John in CR said:
It's not a curse. It's a scam.
No difference. It's necessary if one has assets The alternatives are not using vehicles (impossible in socal) or leaving the area/country. Neither is palatable to me. Of course, it could be legislated; fat chance!
 
2old said:
John in CR said:
It's not a curse. It's a scam.
No difference. It's necessary if one has assets The alternatives are not using vehicles (impossible in socal) or leaving the area/country. Neither is palatable to me. Of course, it could be legislated; fat chance!

The first thing that needs to happen is tort reform. This thing of people "hitting the lottery" when something bad happens to them is ridiculous. Here there's the national insurance company with rates that are quite affordable, and with all licensed vehicles the minimum is liability coverage, which is paid as part of your annual registration fee.

These cyclists who think ebikes should have mandatory insurance but not bicycles is ridiculous. They ride on shared pathways and other places where they are in much closer proximity to pedestrians, so there's little doubt they represent a greater danger to others than ebikes. If insurance should be required for ebikes, then the same should apply to bicycles, mobility devices, and the case could be made for even runners and pedestrians. Where does it stop? I think it has to be with whatever is considered a "motor vehicle" requiring registration and plates in your jurisdiction.
 
Love to see tort reform, but it's probably never going to happen. Whoever heard of someone getting $200 million for using talcum powder? Relative to e-bikes, there's no insurance or licensing requirement for Class 1, 2 or 3 which is the same as for "non-e" bicyclists. This is the law in CA as well as many other states, and seems fair to me.
 
ZeroEm said:
Thinking want a smoother ride, cargo room or good trailer, Maintain 35 mph/56 kph no faster. AWD trike, leafmotor in the back, two grin's front motors in the front, need a good frame and lots of battery.

A KMX with adam333's front and rear suspensions added might work. My only only uncertainty is whether the KMX can use GRIN's front drive motors because of the proprietary front hubs that KMX uses, or whether the aftermarket front suspension kit itself will be compatible with them. The chassis itself is durable and can take plenty of abuse. There are a few KMX trike EVs built to reach 50+ mph and I know more than one with well over 10,000 miles on it.

I only have front suspension on mine and built it into a velomobile, and its ride quality is like a vintage sports car or cheap truck, which, while not nearly as comfortable as a Cadillac or S-class Mercedes, it still well exceeded my expectations for a vehicle that is purely pedal powered. Mine has over 40,000 miles on it, but so far it has been strictly pedal powered with no motor(it has been downhill at over 50 mph).

I also have a 1500W Leafbike 5T wind motor, to be paired with a Phaserunner controller and Cycle Analyst v3 with a torque sensing bottom bracket. All I need to electrify my trike now is a battery pack. Planning to run either 24S LiFePO4 or 20S LiIon. I have the LiFePO4 batteries in my possession, 96 of the A123 26650s, but neither a spot welder nor a BMS since the 24S BMS I ordered is being held up by USPS fuckery over the last 3 months. I have a 20S BMS on the way as well being shipped Express, since I intended to build a LiIon pack in the longer term, but if the 20S BMS arrives before the 24S does, I may buy a no-weld 18650 snap-together kit and some Panasonic NCR18650GAs and finally get this thing converted.

I also have a clamping torque arm made specifically for this trike that bolts to the rear brake caliper mount. I'm planning to put about 7.5 kW peak to this Leafbike motor. I'm confident the trike will be able to take it, as I will not be running up against the boundaries of what it can handle as some members here already have(check out the 10 kW Death Trike, for instance).

Maintaining 35 mph is about the limits of what bicycle-grade rims and tires can handle. Anything faster, and you're going to want moped/motorcycle components. I've thought of eventually getting some 16" motorcycle rims and lacing them to the KMX hubs(bought a spare set of hubs for this purpose, in fact), and building up a 16" wheel in the rear around a 1500W 3T wind Leafbike motor, and putting some Mitas MC2 low rolling resistance tires all around(rated for 62 mph). The unknown is how well these tires roll when being pedaled with no motor on. I want my vehicle to be able to be moved at a comparable speed to a normal velomobile WITHOUT needing the motor turned on, just in case the battery runs out, or something in the EV drive system fails. Likewise, I'll have a throttle to run the EV drive system in case the chain, rear derailleur, or anything in the bicycle drivetrain fails.

Once converted to electric, then I can think of adding some solar panels to the body shell.
 
by The Toecutter » Sep 09 2020 12:50pm

ZeroEm wrote: ↑Sep 09 2020 5:16am

Thinking want a smoother ride, cargo room or good trailer, Maintain 35 mph/56 kph no faster. AWD trike, leafmotor in the back, two grin's front motors in the front, need a good frame and lots of battery.
A KMX with adam333's front and rear suspensions added might work. My only only uncertainty is whether the KMX can use GRIN's front drive motors because of the proprietary front hubs that KMX uses, or whether the aftermarket front suspension kit itself will be compatible with them. The chassis itself is durable and can take plenty of abuse. There are a few KMX trike EVs built to reach 50+ mph and I know more than one with well over 10,000 miles on it.

I only have front suspension on mine and built it into a velomobile, and its ride quality is like a vintage sports car or cheap truck, which, while not nearly as comfortable as a Cadillac or S-class Mercedes, it still well exceeded my expectations for a vehicle that is purely pedal powered. Mine has over 40,000 miles on it, but so far it has been strictly pedal powered with no motor(it has been downhill at over 50 mph).

I also have a 1500W Leafbike 5T wind motor, to be paired with a Phaserunner controller and Cycle Analyst v3 with a torque sensing bottom bracket. All I need to electrify my trike now is a battery pack. Planning to run either 24S LiFePO4 or 20S LiIon. I have the LiFePO4 batteries in my possession, 96 of the A123 26650s, but neither a spot welder nor a BMS since the 24S BMS I ordered is being held up by USPS fuckery over the last 3 months. I have a 20S BMS on the way as well being shipped Express, since I intended to build a LiIon pack in the longer term, but if the 20S BMS arrives before the 24S does, I may buy a no-weld 18650 snap-together kit and some Panasonic NCR18650GAs and finally get this thing converted.

I also have a clamping torque arm made specifically for this trike that bolts to the rear brake caliper mount. I'm planning to put about 7.5 kW peak to this Leafbike motor. I'm confident the trike will be able to take it, as I will not be running up against the boundaries of what it can handle as some members here already have(check out the 10 kW Death Trike, for instance).

Maintaining 35 mph is about the limits of what bicycle-grade rims and tires can handle. Anything faster, and you're going to want moped/motorcycle components. I've thought of eventually getting some 16" motorcycle rims and lacing them to the KMX hubs(bought a spare set of hubs for this purpose, in fact), and building up a 16" wheel in the rear around a 1500W 3T wind Leafbike motor, and putting some Mitas MC2 low rolling resistance tires all around(rated for 62 mph). The unknown is how well these tires roll when being pedaled with no motor on. I want my vehicle to be able to be moved at a comparable speed to a normal velomobile WITHOUT needing the motor turned on, just in case the battery runs out, or something in the EV drive system fails. Likewise, I'll have a throttle to run the EV drive system in case the chain, rear derailleur, or anything in the bicycle drivetrain fails.

Once converted to electric, then I can think of adding some solar panels to the body shell.
Currently run 20S 7P 36A continuous 60A BMS, mated with a Grinfineon 40A for my 7T leafmotor max speed about 33 mph/ 53 kph on flats but 7T drops speed to build power and torque for hills. Only time I drive that fast is out on the hwy's between towns but the speed limit for cars is 45-80 mph so not going to try to drive with them. The vibration on sections of road is bad, blew my 72V-12V inverter. Will start rubber mounting anything like that.

Would like to stick to bike parts, the looks weight and drag. Do think about higher power motors with moped rims. Think the leafmotor is the biggest heaviest bike motor I want to use. If I get off road in Sand or wet ground my trike will start spinning the back tire.

I like the struts on the velomobiles, like velomobiles but it's just to hot here in TX. Read on adam333's front suspension, took notice of him having to drop wheel size to improve steering. Don't think a lot of travel is needed, maybe something like Cattrikes suspension which is more like the performer's headset that I have.

The 5T leafmotor 10.49 Kv in a 26" wheel is a good match for Grin's Fstwind 12.118 Kv (need to find the turn count) in a 24" wheel. Run them all at 74V with three phaserunners. You can have traction, power and speed without huge controller, moped wheels. But very expensive.
 
ZeroEm said:
Currently run 20S 7P 36A continuous 60A BMS, mated with a Grinfineon 40A for my 7T leafmotor max speed about 33 mph/ 53 kph on flats but 7T drops speed to build power and torque for hills. Only time I drive that fast is out on the hwy's between towns but the speed limit for cars is 45-80 mph so not going to try to drive with them. The vibration on sections of road is bad, blew my 72V-12V inverter. Will start rubber mounting anything like that.

You're going to need at least either front or rear suspension, and preferably both. Before I put suspension on my KMX, anything over 20 mph was dangerous, and the vibrations from hitting potholes were more than a little jarring. Unsuspended is also not good for component longevity.

I like the struts on the velomobiles, like velomobiles but it's just to hot here in TX.

I was in Texas by the time I installed my first bodyshell on the trike. Yeah, riding that in the 90+ degree heat in Corpus Christi was quite hellish. I was okay as long as I was moving and getting some cooling air flow, but as soon as I had to stop at a red light, the heat became brutal. At 70-80 degrees, I found it very tolerable. I may add a setup of processor cooling fans, a thermos(to be filled with ice water), and a spray mister to function as a sort of "air conditioning" system.

Read on adam333's front suspension, took notice of him having to drop wheel size to improve steering.

I've found steering to be more than adequate with 20" front wheels, using a 26" rear wheel. My trike is well balanced and corners in a car-like manner. I can pull about 0.6-0.7G lateral acceleration without going up on two wheels.

The 5T leafmotor 10.49 Kv in a 26" wheel is a good match for Grin's Fstwind 12.118 Kv (need to find the turn count) in a 24" wheel. Run them all at 74V with three phaserunners. You can have traction, power and speed without huge controller, moped wheels. But very expensive.

The major downside is that those Grin all-axle motors have thicker 0.35mm laminations that induce more cogging losses than the Leafbike motor. If you ran out of charge or the EV system failed in some way, pedaling that thing home dealing with the cogging losses of 3 motors(two of them being extremely lossy, the other extremely heavy) in addition to the added weight on the trike from the EV system is going to be quite a Herculean effort!

If Grin and Leafbike both made their motors with the thinner 0.2mm laminations or even smaller, I could probably make that sort of system work for my needs. An AWD setup with 3 Phaserunners would be monstrous! Imagine what it would be like to operate that on ice in the winter!

I'd very much like to build up a full-suspension electric velomobile geared to top out at 80-100+ mph and do 0-60 mph in under 6 seconds, and such a 3-motored setup when given the proper selection of motor wind, right battery pack and controller settings would be powerful enough to do it! But if the vehicle cannot be easily pedaled with the EV drive system fully disabled, it defeats the entire philosophy of my vehicle concept, which is off-grid transportation. If the vehicle is functional as a human powered vehicle with the EV drive disabled, then it can still function in a grid-down scenario. You'd have two separate methods of propulsion, that while meant to work in tandem with each other, can by their lonesome still power the vehicle, the worst case operable scenario being you're still faster than a normal bicycle. Add solar panels and now you can still get power even if you can't find a working power outlet. Lots of redundancies built into the vehicle is great for avoiding being left stranded. Having DOT tires and rims on it would further that cause, given that there are no bicycle tires that can stand up well to goatheads littering the road.

I'm going to stick with one rear drive Leafbike motor for the time being for my trike. That said, a friend and I are building a custom 3-wheeled car that is being set up with a Leafbike motor in the rear wheel, and we may put some all-axle front hub motors on the front wheels. The finished car is expected to weigh under 300 lbs, so it would perform at least as well as an average new car from 0-60 with that setup optimized, and because it's not a bicycle, the cogging losses aren't an issue.

https://endless-sphere.com/forums/viewtopic.php?f=34&t=106267

If we do use an AWD e-bike motor setup, we won't be stopping there, of course.
 
I'd very much like to build up a full-suspension electric velomobile geared to top out at 80-100+ mph and do 0-60 mph in under 6 seconds, and such a 3-motored setup when given the proper selection of motor wind, right battery pack and controller settings would be powerful enough to do it! But if the vehicle cannot be easily pedaled with the EV drive system fully disabled, it defeats the entire philosophy of my vehicle concept, which is off-grid transportation.

That thing would be a complete and total nightmare to pedal regardless of how thick your motor lamination are. You'd be better off just walking.
 
sleepy_tired said:
That thing would be a complete and total nightmare to pedal regardless of how thick your motor lamination are. You'd be better off just walking.

Perhaps. Such a vehicle would have to be designed to remain under 100 lbs when the rider is not in it. Even that may not be enough. It's also going to need an extremely wide range for the bicycle gearing, so that power can be added via pedaling through the vehicle's entire speed range, while the low end gearing is low enough to climb a steep hill with the motor disabled. This would necessitate a Schlumpf drive with a triple crankset up front, and a wide ratio cassette in the rear. A 26/39/52T up front with a Schlumpf HS drive that multiplies the speed by 2.5 when engaged and a 34-11T 7-speed cassette in the rear wheel could give adequate range when running a 16" motorcycle wheel(equivalent to 20" bicycle wheel) for the rear drive wheel. 2.7 mph at 60 cadence when climbing a 20% grade with the motors off in the lowest gear, all the way to cruising at 70 mph on the highway at 100 cadence with the motor(s) doing most of the work while being able to even add human power at 100 mph at 140 cadence in the tallest gear... even if in such a scenario human power would be a tiny minority of the total motive force of the vehicle.

Those prototype AMZ hub motors that weigh around 8 lbs and put out close to 50 horsepower peak approaching 98% efficiency that never reached the market are the sort of motors that such a project really needs. You'd only need ONE of them driving the rear wheel to out perform most cars, even though there wouldn't be all wheel drive.

It's a travesty that the primitive Leafbike motor is one of the best direct drive hubmotors available for a bicycle application. We need much more efficient, much lighter hubmotors with reduced iron losses... and the technology for such motors is already old. It's a shame that no one is making them for consumption by the general public.

If Leafbike ever decided to make the highest quality hubmotor they could and target it for the 1st world market, they could price it at double the normal Leafbike 1500W motor and probably sell more than a few of them... I'd very much like to have a DD hub motor that weighed in around 7-8 lbs and achieved peak efficiencies over 95%, that could still be had for under $600. Such a beast would probably grant peak power outputs at least comparable to the normal 1500W Leafbike motor we all know and love...
 
If I was going to build a high speed bike I wouldn't look into using hub motors anymore. I love hub motors for ebikes and other slow moving vehicles, but it's likely that single speed reduction IPM motor of modern design would be much better. Even liquid cooling. No clutches or anything like that there.

Like the newer QS mid-motors or something of better quality. Looks like they have a 7kw version now. Maybe find a motor from a wrecked electric motorbike. Those things should be popping here and there now that electric motorbikes have been around for a while now.

This way you can have the full benefit of field weakening and other more advanced controller features while not giving up very much in terms of simplicity or regenerative braking.

With a full-faired bike about 25 hp would be sufficient to go 100mph on flat ground and no headwinds regardless of weight.

Something along the lines of:

http://craigvetter.com/pages/2015-Streamliner-pages/2015-Vetter%20Streamliner%20history-p81.html
 
The Toecutter said:
It's a travesty that the primitive Leafbike motor is one of the best direct drive hubmotors available for a bicycle application. We need much more efficient, much lighter hubmotors with reduced iron losses...

How much do you think motor efficiency can possibly be improved from 90%?

Hint: not "much more".
 
Balmorhea said:
The Toecutter said:
It's a travesty that the primitive Leafbike motor is one of the best direct drive hubmotors available for a bicycle application. We need much more efficient, much lighter hubmotors with reduced iron losses...

How much do you think motor efficiency can possibly be improved from 90%?

Hint: not "much more".

Mine have peak efficiency of over 95% and get over 90% for the majority of the operating range. That's half the heat of the so called high efficiency Leaf and since my motors run cooler the advantage is even bigger after running a while. Quality motors need to be allowed to spin up to really take advantage of their efficiency, so you've gotta give up the penny farthing size wheels you think are the only ones to run on an ebike.
 
y sleepy_tired » Sep 10 2020 11:39am

I'd very much like to build up a full-suspension electric velomobile geared to top out at 80-100+ mph and do 0-60 mph in under 6 seconds, and such a 3-motored setup when given the proper selection of motor wind, right battery pack and controller settings would be powerful enough to do it! But if the vehicle cannot be easily pedaled with the EV drive system fully disabled, it defeats the entire philosophy of my vehicle concept, which is off-grid transportation.
That thing would be a complete and total nightmare to pedal regardless of how thick your motor lamination are. You'd be better off just walking.

I would not have something like this for joy riding. I get the drag of the motors. This would be added to your stable of bikes/trikes.
My second to next build will be 700C recumbent bike for riding, exercise and distance with 1500w or 1200w max, light setup. 4T leafmotor and baserunner and 50 mile battery.
I need a trike to work not for peddling, racing or distance riding. want to pull trailers for store runs, bike trailer and maybe a person with out peddles. This is down the road at the moment the third build from now. Next is a 29er hard tail for pulling trailers but want to replace it with a trike later.
 
Balmorhea said:
How much do you think motor efficiency can possibly be improved from 90%?

Hint: not "much more".

Your hint is incorrect. There have been off the shelf motors that used to be produced and sold that could do 95% peak and a broad operating range greater than 90%, such as the Hubmonster John in CR mentioned, and used to sell. That's a 6-phase PMDC machine.

There have been prototype hub motors that have approached 98% efficiency such as the AMZ motor I mentioned earlier, but they've never reached the market. 50 horsepower peak in an 8 lb package, less than half the weight of the currently available Leafbike motor that is at its limit just to make 1/4 as much peak power.

Things get very interesting when you consider synchronous reluctance and switched reluctance machines. Broad operating ranges of 92%+ and peaks of 99% are possible with proper attention to the design.

The fact that we are stuck with only dinosaurs on the market is a shame. There's so much untapped performance potential in ebikes if we only had the right components available. The Leafbike motor has a broad operating efficiency of about 80-85% with peaks at about 91%, for comparison, which means a lot more heat that needs to be shed, which in turn limits the peak power and continuous power that is possible.

sleepy_tired said:
If I was going to build a high speed bike I wouldn't look into using hub motors anymore. I love hub motors for ebikes and other slow moving vehicles, but it's likely that single speed reduction IPM motor of modern design would be much better. Even liquid cooling. No clutches or anything like that there.

There are plenty of good choices for running a reduction drive. The Astroflight motors that are available can peak over 95% efficiency, and can pack a lot of power in a small package.

I like hub motors because of their ease of installation and because they are typically designed to work with bicycle drivetrains with minimal hassle, and with less components to fail.

With a full-faired bike about 25 hp would be sufficient to go 100mph on flat ground and no headwinds regardless of weight.

Something along the lines of:

http://craigvetter.com/pages/2015-Streamliner-pages/2015-Vetter%20Streamliner%20history-p81.html

Even this design makes a lot of compromises for the sake of practicality. Being a 2-wheeler and vulnerable to crosswinds, the drag penalty of getting rid of the sides of the faring is easily by a factor of 2.

Entire 4-wheeled cars, like the 1,000+ lb Loremo LS which can seat 2 adults and 2 children, can reach 100 mph on only 20 horsepower.

A trike can offer the sort of stability needed to avoid having to compromise the aerodynamics for the sake of said stability, if you design it right.

There are purely pedal-powered velomobiles like the Milan SL that can do almost 55 mph on 650W of pedal input:

https://www.youtube.com/watch?v=4IHIdGVGKdI

The above velomobile has a CdA of 0.03 m^2. It's using tires with a Crr of roughly 0.004. The velomobile itself is around 70 lbs, plus rider and any items onboard. It can also cruise 30 mph on flat ground at 150W. A modified version of the same velomobile was pedaled to more than 60 mph at Battle Mountain, an annual HPV gathering where riders set records.

Ignoring the aerodynamics of an etrike leaves a HUGE untapped potential for efficiency. Doing a bit of math, if one were able to find some DOT legal moped tires with a Crr of 0.008, and had a vehicle with similar aerodynamic efficiency to the Milan velomobile above, 100 mph on under 4 horsepower is theoretically possible. I do not know if moped/motorcycle/scooter tires exist with a Crr that low, as such tires tend to have a Crr around 0.015+, but there is no shortage of car tires with Crr less than 0.008. The Mitas MC2 are the most promising moped/moto/scooter tire, but the Crr of them is not known, and if it is anything over 0.01, it will be wholly impractical to use for a pedal-powered application.

A single Leafbike motor could really do some wonders for such a vehicle if set up properly. We're talking car-like acceleration with car-like top speed. I've run a simulation of a 3T wind 1500W Leafbike motor with 7.5 kW applied in a vehicle with a 300 lb laden weight and a CdA of 0.03 m^2 doing 0-60 mph in 12 seconds and reaching more than 85 mph top speed without even exceeding what would be the motor's continuous rating at 72V. That said, given the low mass and narrow track of such a vehicle, stability could be an issue at interstate highway speeds. A semi-truck passing by in the next lane might blow the vehicle off the road or into traffic if it is not designed in a wind tunnel to mitigate such a scenario! The center of pressure is going to need to be aft of the center of gravity and sufficient downforce will also be a requirement.

A totally custom design for this application would really be in order, instead of using a design intended solely for human power at lower speeds... and that is where future design iterations of my build are going to come into play, and it's probably not going to be nearly as efficient as a Milan SL velomobile, although such a design could possibly be on the order of comparably slower commercial velomobiles, like say, a Quest or a WAW, while still being practical/safe enough to use for the application. It's going to be an interesting set of experiments.

I just need to get some batteries so I can put my motor in my velomobile, which admittedly, is currently NOT as efficient as even the lower tier commercial velomobiles you could buy, like a Leitra, Cab Bike, or Alleweder. With some refinement to the design, it will get the efficiency to exceed at least those, and it will be necessary for my goal of cruising 30 mph on 300W at the drive wheel. I very much would like to get 200+ miles range @ 30 mph on a 1.5 kWh pack with my pedal input perhaps only accounting for 100W of that! The Leafbike motor is also efficient enough to theoretically allow this.
 
The Toecutter said:
Balmorhea said:
How much do you think motor efficiency can possibly be improved from 90%?

Hint: not "much more".

Your hint is incorrect. There have been off the shelf motors that used to be produced and sold that could do 95% peak and a broad operating range greater than 90%,

Right, the difference between those is 5%. One part in twenty.

Normal users don't have heat rejection as a determining factor in motor efficiency. Lots more folks get by fine with brushed motors that have 60-something percent efficiency, than those who abuse their equipment so grossly as to choose it by minimum waste heat, and risk burning the thing down if anything goes the least bit wrong.

Remember, most of us who speak English at home are limited to 20 mph or less before we are obligated to get licenses and insurance for our rides. Most folks in that general ballpark would rather have a fault tolerant system than a temperamental one that lowers our GVW by a couple of percent.
 
Balmorhea said:
Right, the difference between those is 5%. One part in twenty.

Normal users don't have heat rejection as a determining factor in motor efficiency. Lots more folks get by fine with brushed motors that have 60-something percent efficiency, than those who abuse their equipment so grossly as to choose it by minimum waste heat, and risk burning the thing down if anything goes the least bit wrong.

Remember, most of us who speak English at home are limited to 20 mph or less before we are obligated to get licenses and insurance for our rides. Most folks in that general ballpark would rather have a fault tolerant system than a temperamental one that lowers our GVW by a couple of percent.

You live in Austin, TX, correct? If so, your state as of today only has a 750 watt limit on the motor(before the law changed last year, there was no wattage limit). The speed limit of 20 mph is only if you are not applying human power, but as long as you are pedaling and as long as the motor's power output is not above 750W(whatever the legal definition means, whether that 750W is continuous or peak is not specified), it appears you are legal without license/plates/registration/insurance/ect. In a converted velomobile with a torque-sensing PAS, this 750W gets you up to highway speeds on flat ground, legally, albeit going up hills it won't be so impressive.

The efficiency difference between a 90% efficient motor and a 95% efficient motor won't impact range much, but it can mean the difference between needing a 17 lb motor to run at full legal power limit all day long up a steep hill, or being able to do the same thing with only a 7 lb motor. One will be much easier to pedal than the other if the battery goes dead or if the controller lets the smoke out, rotational inertia being what it is.

For applications like mine, that efficiency difference is much more significant. I'll have multiple settings on my CA computer, including an "off road" mode. It will be set up to be legal when I want/need it to be... but the capability to press a few buttons and be able to dump 7.5 kW to the Leafbike motor will be there, and it will be beautiful... I'd like to be able to have more, without adding weight or increasing losses when it is unpowered...

The extra efficiency is also a boon to the possibility of using these motors in car-like vehicles. A major disadvantage of hubmotors is unsprung weight which adversely effects vehicle cornering characteristics. Significantly lighter motors for a given power output are possible by going from 90 to 95% efficiency. This would open up more design possibilities for efficient ultralight automobiles. Imagine the possibility of building a 400 lb single-person streamliner car that can go for MILES on one cent of electricity, that has nearly 1 horsepower per pound of vehicle...
 
I feel like you're analogous to someone who has a horse, but who instead of riding it, goes to great length to design and build a complex and fragile mechanical capsule around the horse that will allow the horse's natural gallop to carry him at double the horse's natural speed.

I mean, sure... I guess. But at what cost? And in the service of what?

Wouldn't it be easier to simply live closer to the things you want to get to? Or less ideally, take a little longer to get there?

Or at worst, appease your derangement with speed and just drive a godforsaken car?
 
Toecutter,

Don't worry about Balmorhea, it's just a pedalist elitist ebike troll who will never concede a point, despite the fact that its view on efficiency falls apart when a sufficiently long and steep hill comes along or someone wants to build a truly useful car replacement that can carry loads and or passenger without government interference (or is simply incredibly cheap to operate)...It must like riding in inclement weather. Not only does it want to make the rules for everyone else because it knows better than we do, but now it wants to tell us where to live and to use a car like it probably does if we want to go the speed limit. When all else fails it resorts to the snide comments, since there's no way it will admit to being wrong, but that won't stop me from correcting its mistakes about electrics when I run across them.
 
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