[Empact]

This, or a miniaturized version thereof could change the game for light electric vehicles - imagine an electric motorcycle that weighs substantially more like an electric bicycle.

Right now it takes about 10-15lbs of motor to produce a 3KW motor for an electric bike, this motor is about 10 times that in power density afaict.

The Livewire electric motorcycles use something like 100-200 lbs of motor to produce 1/4 as much power, 75kw, so that’s an improvement of 8-16x.

[mywittyname]

Does this motor design scale down? It's not clear from the article - the article focuses more on the relative efficiency gains over the previous model.

A 30lb 1000hp motor doesn't necessarily mean that they can also produce a 3lb, 100hp motor. It would be cool if it did, but I doubt that it does because usually component strength doesn't scale linearly.

That being said, these are still valuable for traditional EVs. Even if they are only a modest weight savings in the grand scheme of modern vehicle weight, their ability to improve packaging options will be a boon. One thing the industry has dicovered is that the generic "skateboard" platform doesn't make for the best vehicles, in terms of packaging.

[NathanKP]

I'm more fascinated by the question of whether it scales up... imagine much smaller and more efficient electric engines for cruise liners and cargo ships.

[jacquesm]

On a cargo ship the last thing you worry about is weight. To the point that they add ballast.

[RogerL]

The article and the press release it was derived from says nothing about "more efficient", just smaller.

https://yasa.com/news/yasa-smashes-own-unofficial-power-dens...

[ApolloFortyNine]

Your average cruiseship already has an electric engine, they just have massive generators onboard to power it.

[lazide]

Notably, it’s probably also not very efficient, and eventually they’ll likely upgrade with some of the improvements from these types of motors to save on fuel.

[kube-system]

Electric pedal bikes are already at the limit of what their chassis’s support even with small motors.

10kw+ is comparable to starter gasoline motorcycles in the US (or midsize motorcycles elsewhere) capable of going on the highway. At that point, you need to start scaling everything, like brakes, tires, and the size of the chassis.

The livewire has a motor large enough to drive a car.

[loeg]

The problem for electric motorcycles is the battery weight.

[bigiain]

That can be offset by not requiring the same sort of range that's typically assumed to be required.

While I'll be likely be riding my ICE bikes for decades because one of the things I do on them is trips with 1000 or 1500km days, truth is the vast majority of my riding is sub 25km round trips from my place. Most of my friends places, a lot of the places I shop or socialise, and the office (which I pretty much never go to any more) fit inside that range. And most of those trips take place on roads with a 60kmh or slower speed limit. _Maybe_ a few short sections of 80kmh.

For all of those short trips, I probably don't even need 2kWHr worth of battery, maybe only 1. The electric motorcycles available around here seem to start at 7 or 8kWHr, and go up to over 20.

The downside to that is the smaller the battery capacity, the smaller the short term peak power it can deliver. The sort of cell chemistry and construction typical in those sort of bikes seem to be limited to 10 or 15C peak discharge, so while their 8kWHr battery can peak at 80kW or just over 100hp, if they downsized the same pack to 1kWHr it'd probably only deliver 10kW peak power.

On the other had, alternative cell chemistry and construction can look way better. I have a few LiPo drone battery packs rated at 60C continuous and 120C peak. A 2kWHr pack of those would give me 120kW continuous and 240kW peaks. Quite likely though at the expense of much greater risks of catastrophic fire. I've had a few of those pack catch fire while charging and one that self combusted in an almost explosion like fashion when I slammed the drone into a concrete pole at about 120kmh. I can totally see why an electric motorcycle manufacturer with warranties and safety reputation and legal/regulatory obligations wouldn't want to accept that risk.

I'd love an electric motorcycle that's "fun" enough to ride, and gets 25km or so reliable range. But it'd need to be at least a bit price and "fun" competitive with my little bikes, a 117kg 125cc ~25kW two stroke and a 138kg 250cc 24kW fourstroke. I have no doubt it'd be possible, perhaps even easy to build an electric bike with the same "fun" power to weight ratio, but right now not down to the sort of price that'd make me take on a project like that.

[kube-system]

25km range is department-store electric scooter territory. A motorcycle that can do highway speeds could expend that entire range in 15 minutes or less, which would be quite a high discharge rate and also an unusual user experience for most.

Maybe what you want is a large electric bike like a Surron or similar?

[DANmode]

Also came to recommend Surron and alternatives.

[loeg]

> That can be offset by not requiring the same sort of range that's typically assumed to be required.

It really can't be offset by that (with current tech). All existing electric motorcycles are both overweight and very limited on range.

[jacquesm]

Indeed, more so because that weight tends to be further off the ground than in a car.

[loeg]

Well, and the fun ones are power-to-weight monsters. Making them 100 lb heavier (and neutering range) is a recipe for a less exciting motorcycle. Might work for something like a Gold Wing (though limited range would also be a problem there).

[DANmode]

Ten years ago it was a problem.

Good, even some great, stuff out there, today.

[loeg]

It's still a problem today, 2025. I think the LiveWire S2 models come closest, but they still have anemic range. (And we're ignoring cost, which is also much higher.)

[DANmode]

Problem implies “it’s not happening”.

Cost is a challenge.

These things go 175 miles, up to 450+ miles if you have money.

[loeg]

I mean, sales are largely "not happening." Livewire sells ~600 bikes a year. Buyers have the same objections I do.

> These things go 175 miles, up to 450+ miles if you have money.

Only the heaviest models, ridden extremely conservatively.

[DANmode]

> Buyers have the same objections I do.

Buyers don’t know they exist, if they’ll struggle to register them, or how to work on them!

The heaviest ones seem like the same weight as a 600cc or 1000cc crotch rocket - am I missing something big?

[soperj]

> This, or a miniaturized version thereof could change the game for light electric vehicles - imagine an electric motorcycle that weighs substantially more like an electric bicycle.

Sounds terrible for every other user of paths currently.

[mperham]

There’s no area in the world that allows e-bikes with more than 750w motors. A 3kw motor is illegal (cf Surron), unless you are talking about an e-moped requiring registration.

[SR2Z]

They are not allowed, but still commonly owned and used.

The law needs to catch up. There are clearly good reasons for people to want extremely powerful e-bikes and they should be allowed to. They can't be treated like bicycles because they're too fast but aren't nearly as dangerous as motorcycles. We need a new category for light motorcycles.

The real problem, IMO, is that the law is generally not deferential enough to cyclists and already forces them off sidewalks, onto the street, and to follow traffic laws designed for cars. There's not much else to take away, and the rules right now are unreasonable enough that cyclists always break them.

I think what I would like to see are explicit requirements for insurance and licensing for powerful e-bikes, but made significantly cheaper so that people will actually bother. Requiring helmets for the insurance would also make it much more straightforward. We can require them to take the street or a dedicated bike lane and fully mandate that they have to be walked on sidewalks.

[bootlooped]

> The law needs to catch up. There are clearly good reasons for people to want extremely powerful e-bikes and they should be allowed to.

I'm not so sure about that.

I don't want a 6000kw Sur Ron riding in the bike lane with me. The whole point of the bike lane was to make a safe space for riding a bicycle. I want the bike lanes to be safe enough for children to ride their bikes in, and having something that powerful in it is not conducive to that goal. They are by and large too fast and too unlike a bicycle for bike lanes. Having things that powerful there is going to dissuade a lot of potential (non electric) cyclists. My girlfriend already gets too freaked out by how fast some of the legal e-bikes in the bike lane go.

Certainly they shouldn't be on the sidewalk. But what does that leave? Just the road. If that's the case they probably need to just adhere to whatever standards the state has for scooters or mopeds. Which probably means some kind of license, maybe registration, and possibly insurance.

But that type of e-bike manufacturer doesn't want to make a light electric scooter that's road legal, they want to make a thing that skirts regulations by being "for off road use only".

And the buyers by and large don't want to deal with license and registration, and certainly not insurance.

Just because people are doing an illegal thing a lot doesn't mean that the law needs to find a way to make it legal.

[icedrift]

I think what they mean is these e-bikes pushing 60mph should be legal but reclassified as something closer to a motorcycle. The problem with keeping them illegal is people tend to treat them like bikes when they should be on the road.

[rounce]

This is already handled in the licensing in the UK and Europe it’s an A1 motorcycle license if it’s below 11kW, A2 up to 35kW, and everything over is the full-fat A license.

[SR2Z]

The law either needs to make it legal or properly be applied to everyone. The worst situation is when an unenforceable law which does not have the teeth for a situation is on the books - it's the same as it being unregulated, but now the government can fine you whenever it wants.

[jlarocco]

> but aren't nearly as dangerous as motorcycles.

What a ridiculous statement.

I don't think there's any inherrent difference, but until the laws catch up the "powerful e-bikes" are clearly more dangerous. Riding a traditional motorcycle requires a license, passing a driving test, and following the rules of the road - none of which are true for e-bikes.

But I'd love to hear why you think the opposite.

[lelandbatey]

An ebike weighs less than a motorcycle by at least half (for super lightweight motorcycles) or less than 1/6th the weight. So a fast ebike is about as dangerous as merely the human person +100lbs traveling at speed.

Thus, less energy to transmit to a pedestrian

[jlarocco]

100 pounds of bike plus 150 pounds of person hitting a pedestrian at 30+ mph is still going to do cause serious injuries to both of them.

But it's really a moot point because there are essentially zero motorocycles travelling on sidewalks, bikepaths, and trails where pedestrians are going to be concentrated, while it's a free for all for e-bikes.

In general, motorcycle/pedestrian accidents are pretty rare. Statistically, motorcyclists are most likely to injure or kill themselves rather than bystanders.

[SR2Z]

Yeah, it's not going to be as bad as a 300lb bike and 150lb person with a fuel tank in the back...

There are lots of gas powered motorcycles in the bike lanes where I live. Not legal, but nobody enforces it.

[earleybird]

And still fatal

https://www.ctvnews.ca/vancouver/article/pedestrian-dead-aft...

In this case it was a bicycle and not an ebike. That said, anecdotally, many ebikes I see regularly travel faster than the people powered versions

[consp]

> There are clearly good reasons for people to want extremely powerful e-bikes and they should be allowed to.

They are called motorcycles. At > 4kw they are that (here). So either you get them registered a such, get a license and insure them, or downgrade them to under 4kw, get a license and insure them as a moped, or downgrade them to 2kw and pedal assist only and register them as a pedelec. All other options is 250w continuous (you can get away with about 500w peak) and pedal assist only.

You are also not insured if you drive an illegal bike on the road.

[Aurornis]

> The real problem, IMO, is that the law is generally not deferential enough to cyclists and already forces them off sidewalks, onto the street, and to follow traffic laws designed for cars.

If we’re talking about high powered e-bikes, I don’t want them on the sidewalk either. Once they exceed the current regulations they’re in the moped/motorcycle category.

> There's not much else to take away, and the rules right now are unreasonable enough that cyclists always break them.

So what’s your suggestion? Let people ride electric motorcycles on sidewalks? Change the laws so that high powered e-bikes don’t have to follow the rules of the road?

I don’t think the current laws are unreasonable. I live in a place where people routinely ride their e-bikes on the sidewalks and it’s absolutely awful, especially with young children. Every time we go somewhere I have to hold their hands and yank them off the sidewalk at least once to dodge another e-bike zooming past. I can only hope enforcement catches up and starts impounding bikes from people breaking the law and issuing large fines, because I don’t know how else to stop this.

[SR2Z]

No, electric motorcycles should not be on sidewalks - but regular bikes can be.

[oblio]

Any ebike that goes faster than 25kmph in Europe and whatever it is in NA should not be allowed anywhere were pedestrians can go.

The real solution people don't want to accept is that ALL non arterial roads in ANY urban/suburban/rural environment should be limited to 30kpmh (and equivalent in NA). And by limited I mean traffic calmed: 1 lane per direction, narrow lanes, raised street crossing, raised intersections, European style roundabouts, the works (Dutch style) - so that people actually respect the speed limit because they don't want to bang their car.

Once that happens, bike stay in bike lanes (or multi use paths with pedestrians) and everything else can go on the regular non arterial roads and stuff that's registered (mopeds and up) and go on any road.

But my "solution" requires major political adoption and probably decades of sustained vision in investment. In places with good governance it will happen naturally and everywhere else will slowly be left behind.

[ashirviskas]

> Any bike that goes faster than 25kmph in Europe and whatever it is in NA should not be allowed anywhere were pedestrians can go.

So, literally any bicycle?

[jlarocco]

As a cyclist, motorcyclist, and potential e-bike owner, I'd actually be in favor of making it any bicycle.

Anybody moving significantly faster than the flow of traffic is endangering the rest of the users.

[oblio]

I meant fast ebike.

Bikes should be allowed on shared use pathways and all sidewalks larger than 2m should by default also allow bikes.

Mopeds should be banned and fines should be big, to discourage that kind of use.

[oblio]

Fixed.

[nandomrumber]

It’s only one step away from full zero road deaths.

I propose that in order to be able to leave your house people should have to have a valid reason, have done a course, and apply for a single-use permit.

Because, obviously, people can’t be trusted to do the right thing, ever, and one death in the community, for any reason, ever, is too many.

[oblio]

I'm talking about Dutch style safety measures.

Fairly sure the Netherlands is a more advanced democracy than the "my freedumbs" US is at this point.

And Dutch infrastructure is also better.

[ghostpepper]

> They can't be treated like bicycles because they're too fast but aren't nearly as dangerous as motorcycles.

Why would an extremely powerful ebike be any less dangerous than extremely powerful gas motorcycle?

[SR2Z]

It will weigh like 3x less.

[ericd]

>They can't be treated like bicycles because they're too fast but aren't nearly as dangerous as motorcycles.

As a former rider, why? Cars were the most dangerous part, in my experience.

Something that stuck with me from my motorcycle safety course, the speed at which hitting a wall is 50% fatal is 30 mph. Doesn't take highway speeds.

[SR2Z]

The goal is not to protect the people on motorcycles, who (if we're being brutally honest) forfeited most expectations of safety as soon as they got on their bikes.

The goal is to protect the regular cyclists and pedestrians who they currently share paths with while trying to not make them TOO unsafe.

[jacquesm]

> aren't nearly as dangerous as motorcycles.

Opinions differ. I have seen far more accidents with powerful e-bikes than I have seen with motorcycles, and yet there are many more motorcycles.

[SR2Z]

This likely depends on where you live. Where I am (SF) ebikes do definitely outnumber motorcycles.

[Empact]

In many states there’s a carve out for mopeds, for example which have less than 50 ccs of displacement. In Texas you can ride them with just a regular drivers license, but ccs have no meaning in the electric world. Should be straightforward to make the case for equivalent regulation, but would require a new advocacy campaign/org.

[bhhaskin]

There is a big issue in the US currently with people buying electric motorcycles that look like e-bikes.

[eikenberry]

What is the issue? I've seen people on those bikes and they look fun to ride.

[RajT88]

I see kids blasting around at high speeds without helmets.

Kids treat them like fast bikes you do not have to pedal. Wiping out on a bike at 13mph is a very different proposition to wiping out on a bike at higher speeds.

I saw just a couple nights ago some kid doing what appeared to be about 40mph on an eBike. Wind in his hair, not pedaling, just blasting it. I am sure new regulations will come to speed limit them, but at the cost of dead and disabled young people.

ETA: I went to go look up laws requiring speed limiters on bikes, and the top hit was about how you can disable them:

https://goebikelife.com/how-to-remove-ebike-speed-limiter/

Article states typical eBike speed limiters are 20-28mph. That is the kind of sustained speed Olympic cyclists can maintain for some period of time, and much faster than kid's toys need to be capable of. And these are the mandated limiters!

[jacquesm]

A kid died right in front of my door on one of those. They call them fatbikes around here and they're super dangerous to operate. Way too much torque and speed for kids (and, fairly, most adults) to handle responsibly.

[RajT88]

See - you nailed it. I did plenty of dumb shit when I was a kid, but like the specific number I quoted - 13mph - wiping out at that speed, which I have numerous times even as an adult - is a totally different level of bodily harm compared to the speeds I see kids doing on eBikes.

Would I have as a kid blasted around at 40mph if I could have? Goddamn right. That's actually my point - I'm not dead or permanently damaged, just the recipient of quite a lot of road rash. Worst injury I ever had on a bike was a broken trapezium, as an adult, for something totally not speed related (~13mph, yes), when a tree fell in front of me and I braked and flew across the handlebars. Game that out doing even 20mph and that's a different outcome.

Classic case of, "I've been there, done that, and this situation is nuts".

[bhhaskin]

And here is the problem. They are already supposed to be speed limited if it's an e-bike. It's easy to tell the difference between a bicycle and a motorcycle, but the difference between an e-bike and electric motorcycle is far more subtle. And most electric motorcycles lie and market themselves as e-bikes.

[RajT88]

> And most electric motorcycles lie and market themselves as e-bikes.

Because they have pedals which nobody uses. In theory, it's pedal assist, but kids aren't really pedaling eBikes, they are using them like electric motorcycles.

You might think: Hey, how can you tell the difference between somebody using an eBike with pedal assist if so many of them look just like regular bikes?

I don't really see young people pedaling bikes at all of any kind. It's adults who don't have cars, or adults who are exercising pedaling bikes.

[eikenberry]

On a decent hill you can get a regular bike going >60mph. A dirt bike will let you ride off road at nice speeds over random terrain (no licensing required when not on public roads). In the realm of bikes, these are not an outlier. Limiters are easily overcome and speed limits are barely enforced on cars, let alone bikes. When you get a bike like this you deal with the danger and wear protective gear just like you would with any other bike (motorized or not).

[ghostpepper]

> On a decent hill you can get a regular bike going >60mph.

This is not the same as being able to go > 60 mph anywhere, at any time, simply by pressing a button.

> When you get a bike like this you deal with the danger and wear protective gear just like you would with any other bike (motorized or not).

This only deals with the danger to the rider - it doesn't address the danger to pedestrians.

[gambiting]

>>On a decent hill you can get a regular bike going >60mph.

Yes, I've done this before by riding all the way up a local mountain on a road bike, clad in lycra, then on the way down I went over 60mph. It was terrifying and the physical fitness required to get up there in the first place required months of riding to actually do it. Meanwhile literal kids ride these on pavements, in between people, in cities where pedestrians walk - it's simply not acceptable. And I do own and ride an ebike(limited to 15.5mph) legally.

[umanwizard]

Sure, there exist hills where some reckless people who refuse to brake can hit 60mph/100kph on a classical (non-motorized) bicycle. Unfortunately it’s difficult to prevent such stupid behavior, but thankfully, the places where it can happen are severely limited.

Therefore, we should count our blessings that it’s not more common, rather than allowing devices that enable it.

[Animats]

> I saw just a couple nights ago some kid doing what appeared to be about 40mph on an eBike. Wind in his hair, not pedaling, just blasting it.

Saw an ebike zip past me at about 40 MPH in a wheelie, little motor screaming, splitting a lane in traffic. (El Camino Real, Silicon Valley). If anything happens ahead of them, they're toast. Can't stop and can't evade.

[cwmoore]

Electric bikes offer new opportunities for built-in cigarette lighters in the space. These kids...

[CamperBob2]

Kids these days

[nsxwolf]

My neighborhood is full of kids on these things. The safety dynamics of driving around have changed completely. Small children flying on and off road at high speeds. It's crazy.

[Rebelgecko]

The issue is they're mostly ridden by teenagers with still-developing frontal cortices. The death rate is still lower than cars, but they're much more dangerous than a "real" bike (or ebike)

[rconti]

Okay, but is it difficult to extrapolate the weight saving benefits of a "legal" power e-bike motor?

[carlosjobim]

He said motorcycle. That's a market of hundreds of millions to one billion customers.

[beefnugs]

Oh nooo i have to put a sticker on it, and only allow my control to go to some arbitrary value when the cops are watching

[MadnessASAP]

Listen, your world may not allow you to sell an e-bike with a 1000hp motor on it. But my world allows me to put a 1000hp motor on an e-bike and not tell anyone.

Now hold my beer...

[doubled112]

There's a difference.

I've noticed that people seem to believe as long as they bought something it should be safe. If you're smart enough to build something, I have to hope you're at least smart enough to realize that there might be consequences.

Take your beer back, I'm going for a rip next.

[usrusr]

So that you can flip over in an uncontrolled wheelie at an even lower fraction of the throttle? Even if there was infinite energy throughput (aka power) at zero mass, the main limiter for power per total system mass would still be the battery. In any practical setup, even in super short runtime designs, getting, say, twice the power would not all that dramatic a runtime hit if it was achieved by scaling the same motor technology and paying for the extra mass with a little battery capacity. Unless of course you want to actually use that power increase for any meaningful fraction of the runtime, then you'll obviously drain the battery fast. But a zero-mass power increase would not change that a lot either.

Increasing power density (of the motor) just isn't worth much when it does not happen to coincide with an increase in efficiency (and then the battery mass saved for achieving the same range will quite literally outweigh the mass saved by a smaller engine for achieving the same power)

The good news is that those striving for power density aren't really at liberty to completely ignore efficiency in the process because cooling is a key issue for them.

[lazide]

Honestly he’d probably just pretzel the frame underneath him, assuming he gunned it.

That’s enough power to potentially do that to a full size car frame.