What a dumb looking bike

An internally geared hub would add even more drag on top of the shaft drive itself.

Bike chain with derailleurs: ~3% power loss

Shaft drive: ~10% power loss ( assuming we have an angled drive )
+
Rohloff: 6-10% loss ( note, this is exceptionally efficient for a geared hub )
= 18% power loss

Can't really afford to waste electric/human power that much.. that's why nobody buys shaft drives.
 
An internally geared hub would add even more drag on top of the shaft drive itself.

Bike chain with derailleurs: ~3% power loss

Shaft drive: ~10% power loss ( assuming we have an angled drive )
+
Rohloff: 6-10% loss ( note, this is exceptionally efficient for a geared hub )
= 18% power loss

Can't really afford to waste electric/human power that much.. that's why nobody buys shaft drives.
And it's likely why the guy in the video had such a hard time with the bike in pedal-only mode.
 
An internally geared hub would add even more drag on top of the shaft drive itself.

Bike chain with derailleurs: ~3% power loss

Shaft drive: ~10% power loss ( assuming we have an angled drive )
+
Rohloff: 6-10% loss ( note, this is exceptionally efficient for a geared hub )
= 18% power loss

Can't really afford to waste electric/human power that much.. that's why nobody buys shaft drives.

I guess I still think it could serve a purpose, but it will be extremely limited. Just as people who do long distance trekking love their belt drives just because of reliability not because of their efficiency.

The ebike equivalent of a hummer so to say ( or Land Rover ). Not the most efficient for highway use, but very much suited for rugged terrain. Also probably not practical for anything else, just like one of those Hummers.
 
Edit: shielded chains have been around for ages, but you're required to use a gearbox not a derailleur
That's no different than the shaft or belt drives, so not a disadvantage really. If you are looking for something less environment-susceptible, but still "efficient" and easy to deal with roadside, that's probably your best combination of the already-discussed technologies.
 
And it's likely why the guy in the video had such a hard time with the bike in pedal-only mode.
I suspect the motor and bearings of the "wheel" ;) had a lot to do with that too.

If it's a direct drive motor, then at the large diameter there would be a lot of magnets, and a lot of stator teeth, and a lot of drag from just that.

Whether it is a single large bearing with needles or balls, or a bunch of small ones, that's a lot of bearing friction, too--especially if they greased them instead of a light oil coating.

I didn't watch the video: Did he ever show just hand spinning each wheel off ground, and the spindown time? If so, you can compare the front to the rear spindown time to figure out how much the motor and/or pedal-interface has to do with it, vs the bearings. If the time is the same, and short, the bearings are probably simply awful, which isn't unexpected. If the time is shorter for the rear, but stil short for both, then that's the motor / pedal interface *and* the bearings. If the front spins a long time then the bearings are not that bad and it's just the motor / pi.

The pedal interface should have some sort of freewheel or clutch in there so the wheel doesn't backdrive them and trigger the PAS, causing the motor to run by itself...but given the comments here I expect there either is no freewheel or it is greased so heavily that it is dragging the pedals along anyway, so it's also adding drag to the rear wheel.
 
I didn't watch the video: Did he ever show just hand spinning each wheel off ground, and the spindown time? If so, you can compare the front to the rear spindown time to figure out how much the motor and/or pedal-interface has to do with it, vs the bearings.
He did it with just the rear wheel, which only kept spinning for like a half turn after a good push. An insane amount of drag/stator teeth/bad bearings. Who knows.
 
Half a turn? Wow that is AWFUL with a capital POC. ;)

If it's from the motor drag, then while hte motor is in use that might be mitigated enough to not affect power usage / range much, but I wouldn't expect that.

This thing sounds like a much worse design and engineering fail than it seemed when the ad was posted way back when, and it seemed pretty bad already.

What I'd like to know is where the six million bucks went that they made from KS. If I had that much for my wolfy project, I could probably pay a real programmer to do it, a real roboticist to build it, and have money left over to have some of them made by a real manufacturing company to give away to those that need them, and possibly live the rest of my life on the remainder!
 
I guess I still think it could serve a purpose, but it will be extremely limited. Just as people who do long distance trekking love their belt drives just because of reliability not because of their efficiency.

The ebike equivalent of a hummer so to say ( or Land Rover ). Not the most efficient for highway use, but very much suited for rugged terrain. Also probably not practical for anything else, just like one of those Hummers.

I'm still trying to figure out what the purpose is other than being different.
There's too many downsides vs upsides on shaft drive.

Chains can last a long time on a regular bike, even longer with appropriate dust shields. Classic Dutch bikes had some good ideas here.

1737398523093.png
 
Chains can last a long time on a regular bike, even longer with appropriate dust shields. Classic Dutch bikes had some good ideas here.

View attachment 364570
Yeah, those are awesome for chains, but miserable for mechanics. They're one of the reasons a "Dutch style" flat fix means patching the tube without taking the wheel off. It's a nuisance, but not as much as taking the wheel off.
 
I'm still trying to figure out what the purpose is other than being different.
There's too many downsides vs upsides on shaft drive.


The only use I would have for a (sealed) shaft drive on a rear wheel is if it's for offroad conditions that would destroy a chain or belt drive even with enclosure (liquid mud, etc).

For a front wheel drive where the powertrain (pedals, motor, whatever) has to go up and over and around the steering / headtube, a short small shaft that's really just a U-joint is useful (like the TruckTrike (triketruck?) used). But it's not really a shaft drive per se, in the way that's being discussed here, as a regular chain or belt would still be used to get the power to the input of the shaft, and from it's output down to the wheel.
 
Chains can last a long time on a regular bike, even longer with appropriate dust shields. Classic Dutch bikes had some good ideas here.

Yeah, those are awesome for chains, but miserable for mechanics. They're one of the reasons a "Dutch style" flat fix means patching the tube without taking the wheel off. It's a nuisance, but not as much as taking the wheel off.
There are solutions possible to minimize this, by making the rear section of the cover detachable. That'd be more complex for a cover with a lubrication bath, or a chain that has a lot of lube on it that could get dirty during the repair (or get the person doing the repair lubed), especially if roadside.

If the detach can be done toollessly it'd be easier to use but harder to design/make. If it's a simple tool that is already part of what's used to do the wheel removal and/or repair, then it's nearly the same as toolless.
 
I'm still trying to figure out what the purpose is other than being different.
There's too many downsides vs upsides on shaft drive.

Chains can last a long time on a regular bike, even longer with appropriate dust shields. Classic Dutch bikes had some good ideas here.

View attachment 364570

Those are exactl;y the type of chain guards I can't stand. They do not really protect against ingress and to 'combat' that they used to pack the 'inside' with copious amounts of lubricant.. I feel it's like the old style shifter/brake cable layout, where we had multiple segments of outer cable -> multiple points of dirt ingress. In my experience they aren't durable, their mounting system is often flimsy and they can not withstand any 'abuse' which in a bikes lifetime is sure to happen ( not a matter if, but when ).

The only use I would have for a (sealed) shaft drive on a rear wheel is if it's for offroad conditions that would destroy a chain or belt drive even with enclosure (liquid mud, etc).
Well yeah. Situations where efficiency is down on the list vs being able to traverse that specific terrain efficiently ( as in, you might use a lot more power, but you'll actually get where you want to go reliably ).

I'm still trying to figure out what the purpose is other than being different.

Well just like riding around with a hummer, I guess riding on such a bike would make people feel 'different' lol. Not my intended use, not when I would rather have better range and a lighter bike since I am not traversing Utah salt plains or something ( I seen video's of what that stuff would do to any chain or belt drive, and that's where I think it would make sense other then being different ).
They're one of the reasons a "Dutch style" flat fix means patching the tube without taking the wheel off.
.. wait that's actually called a 'Dutch style fix' 😂

Never realized.. I mean I have done the same all my life with department store bikes ( bolt on wheels ). I assumed it would have a more internationally recognizable name like 'BSO style fix' as indicating the lowest style of bike one can buy.
 
The chain drive, even with a derailleur, is just unbelievably bulletproof. It tolerates a lot of abuse and neglect, i think salty slurry in winter is the worst enemy. Will not break just because offroad (check out cyclocross). And of course 'better' is the enemy of 'good enough' - like these new 1x12 (1x13?) developments that wear out so fast and cost so much to replace..
 
There are solutions possible to minimize this, by making the rear section of the cover detachable.
They almost all have a tailpiece that comes off easily. It's not so much removing that, but removing the wheel and reinstalling the chain after removing the wheel that is the problem. Especially if it comes off the front chainring along the way.
 
And of course 'better' is the enemy of 'good enough' - like these new 1x12 (1x13?) developments that wear out so fast and cost so much to replace..

Hopefully what's old ( 21 speeds ) is new again someday? 😅

018-trek-monster-track-dc-atbCOVER.jpg
 
Yep, pretty sure someone will invent front gear shifter in few years. But it will require a new frame design so you'll have to buy a new bike.
And the one on your pic - it's the AK-47 of bikes, will take everything..
 
What I'd like to know is where the six million bucks went that they made from KS
He covers his opinion of that in the video, and I agree with his conclusion: they spent it. Dozens of people had to design and integrate all those bespoke custom parts, from the thumbprint sensor to (admittedly cool-looking) light housings. Programmers for custom firmware and a bad app. Tons and tons of fake PR to hype the bike up, he mentions how all the initial reviews of it were "good," which sounds like paid-for advertisement. And in the end, they did actually produce several hundred of these things, if not up to 1-2k of them. I think a combination of all those things, plus bad financial management, just means that $6mil went fast. In other words: not a scam, just dumb money.
 
Yeah, a better scammer wouldn't of bothered to build an actual bike. "Ten by noon, then the moon", as they say.
Those bikes might become a collector item. I can see some future movie with a scene of people riding those bikes to show what dorks we were in 2025.
 
They tried to leapfrog every component of a bicycle. I doubt they had much experience riding or building bikes. They faceplanted.

The sad thing is you would never get $7mil to logically improve diy bikes. For that amount you could build a very solid wiki for vesc, order a few shipping containers of purpose built chromoly or stainless frames from Maxway Taiwan, have a top quality XXFirm coil produced to drop in to the Suntour forks that are everywhere, etc etc etc

With the legal crackdowns on Surrons coming, I'm hoping big money flows into diy and we start advancing like the light emoto segment recently has.
 
With the legal crackdowns on Surrons coming, I'm hoping big money flows into diy and we start advancing like the light emoto segment recently has.
I might be out of the loop, which legal crackdowns on surrons are coming?
 
I might be out of the loop, which legal crackdowns on surrons are coming?

California is the big one recently, but many municipalities are hammering down the classes of ebikes. With the direction those bikes are going, putting kids on top of 10kW+, I don't really blame them.

The law is anything on the road going over 20mph must have pedals and no throttle, peak power of 750w. They are just gonna mean it more now...depending on where you live.
 
The law is anything on the road going over 20mph must have pedals and no throttle, peak power of 750w. They are just gonna mean it more now...depending on where you live.
Sounds like a great opportunity for e-bike commuters to stage another protest like San Francisco cyclists did after being cracked down upon by police for rolling through stop signs:

Just have a preponderance of e-bike commuters take the traffic lane and stay under 20 mph. Hey, they said we had to. We're just doing as we've been commanded.

That said, anybody who didn't see this kind of thing coming when crappy little motorcycles started trying to pass for e-bikes, isn't firmly grounded in reality.
 
That said, anybody who didn't see this kind of thing coming when crappy little motorcycles started trying to pass for e-bikes, isn't firmly grounded in reality.
same thing here with all those anti social youth on their fatbikes :)

Regulatory crackdown only happens when enough people get pissed at something... or that's how it works here, over there I fear it might be more important which people you piss off and not so much how many.

San Francisco Police Department's (SFPD) Captain John Sanford called for the crackdown(link is external) in June after witnessing cyclists overtaking him in the Park District. "I'm in an unmarked black police car, and they're just zipping past," he said.

"bicyclists are required to follow the rules of the road," Sanford said. "There's a thing called a stop sign that bicycles are supposed to stop at."

.. seems I was right, sad.
 
They can pass all the new laws they want. I'm in the "OC" and there's virtually no policing of the current laws (for instance: under 16 need to wear a helmet) not to mention 28 mph is allowed only with a PAS system on a path contiguous with a road or on a road.
 
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