What is the definition of an endless sphere "motorcycle" vs "ebike"

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Dec 25, 2010
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I want to make sure I design my high powered ebike in such a way that it is classified as both an ebike and a motorcycle.. the build thread will be in the ebike forum, not motorcycle, so I need to know where gray area becomes especially gray.

has pedals and ability to be powered by human only
has a battery and motor of a certain size and weight (with continous power and peak power limit for each)
has a ebike mode that is level 3
has a motorycle mode that is 100kW?
below a max weight for ebike
 
My metric:
- is it on a bike frame?
- does it have a working flinstone drivetrain, which gets used?

If so it's a bike.. with a lot of power.

Legality? this depends on your country's laws.. we're an international forum where members may have a 250w limit and cops dynoing bikes that go too fast.. or they may live in a place with zero laws or just no enforcement.. so it would be impossible for us to have a forum-wide legal conception of what is a bike and isn't.. that's between you & your local lawman.

Also a very small number of people have filled out what country they are in.. so such discussions can get silly quick..
 
I feel like most DIYers take advantage of not limiting themselves to the class restrictions. So personally I'd consider something a motorcycle if you sit down to ride, but the pedals are missing or just useless things tacked on for legalities. Like Super73 frames where you can't even move the seat up and down and look like a waddling duck if you pedal. That's obviously just an unlicensed motorcycle hiding behind a legal scam.
 
My metric:
- is it on a bike frame?
- does it have a working flinstone drivetrain, which gets used?

If so it's a bike.. with a lot of power.

Legality? this depends on your country's laws.. we're an international forum where members may have a 250w limit and cops dynoing bikes that go too fast.. or they may live in a place with zero laws or just no enforcement.. so it would be impossible for us to have a forum-wide legal conception of what is a bike and isn't.. that's between you & your local lawman.

Also a very small number of people have filled out what country they are in.. so such discussions can get silly quick..
Yeah, but I read his question as meaning how does this web site distinguish, so he can put his thread in the correct forum.

I don't think that's subject to international law.
 
I feel like most DIYers take advantage of not limiting themselves to the class restrictions.

The same thing is happening with pre-builts:


I've also seen something approaching this on cheap Chinese pre-builts where it will have dual fat bike hub motors, dual beefy batteries and dual beefy controllers.
 
How this web site classifies them is similar to how i do.. loosely!
Okay for something to be slightly miscategorized if it is some weird gray area.

To put it to test.. i built a 60mph ebike.. all the parts were bike parts.. the frame is a bike frame.. it has a huge chainring and i pedal it.. there's no VIN..
We'd consider it a bike based on what kind of part it uses.

Conversely, you put pedals on something with a motorcycle frame and parts? it's still a motorcycle because the majority of it is motorcycle.

These prebuilts that don't have a VIN and yet aren't legally an ebike? it's a case by case basis.
 
I think an ebike has pedal power in addition, a motorcycle doesn't. Now, there are some "ebikes" that are capable of motorcycle speeds, but if you're doing that you're just reflecting a lack of two wheeled intelligence.
A motorcycle with pedals is stooopid.
 
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I think there is an exception. A beautifully packaged 30kW powertrain in a track bike style bike, with 29er 2.4" slick schwalbe tires, dual hub motors (15kW each).. dished wheels to hide the enormous motors with distributed batteries like copenhagen wheel, but well thermally isolated. This is a bicycle that can be registered as a motorcycle. A Class 4 ebike, imho. A stealth motorcycle
 
Put it in the bike section, because that's it's form factor.
Good luck registering it, the bike will probably need a VIN, which is hard to come by for bicycles :)
 
Alright, I’ll bite.

I’m glad you put a question mark after “100KW”.

But fat tires in a track frame?

Front disc wheel? Outdoors!!??

Enormous backpack battery?

I think you need a velomobile to hide the quantity of copper and lithium you’ll need for such a project.
 
The battery and inverter can be in the wheel. 700cc wheels are huge. They will be $5000 wheels, for sure. at least. Yes fat tires in a track frame, it will be a beefy track bike. The geometry will be the same. No it won't go to orbit. 8kW in a 700c mountain bike didn't orbit, not even close. 15kW it might start to lift a little bit, I'm thinking it might be possible to build the front wheel more powerful than the rear so that traction in the front is never an issue. maybe 22kW front 8kW rear. Can put the battery in the front wheel, and inverters in the rear to keep the weight on the front tire. run all the phase wires through the frame towards the front.

Think 600mm-650mm diameter motor with 400-500mm ID

Yeah this will look like a cartoon version of an track bike with large features.

Screenshot 2024-11-12 112632.png

View attachment 361830
 
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So you're going to manufacture or have manufactured every piece of this bike from scratch basically.. motor, frame, maybe even tire?

Consider that your ride quality on this bike is going to be extremely poor and you will regret not adding suspension.. but then, even if you do, you have massive unsprung weight that would make that suspension useless..
 
The challenge to make the wheels light is a great challenge to have. Carbon fiber. It'll be a great way to spend all my life savings and a great way to lose my life in the process.
 
Well, the ends of the IQ spectrum have this to say:
9a4ck7.jpg
 
Batman bike.

It’s feasible without the front wheel. That’s a non-starter. Rough prototype of just the wheel plonked in a regular bike will quickly convince you of that. By rough, I mean just screw thin ply discs to either side of a spoked wheel, then squirt concrete into the cavity they form.
 
cromotor wheel was like 30lbs double the active material, 45lbs. I think it could be heavieer if the tires are beefier. Maybe will cast polyurethane 75A.. Keep things interesting.

I asked schwalbe for custom tire.. you can guess what they said
 
Grin all axle, fat edition are something like 11lbs each and power equivalent to a cromotor.
Try to get your hands on some high end molicel and stuff every last inch of the bike's triangle. With a large-extra large frame, probably 3kwhrs could be fitted.

Now we've got the bike you wanted without dissolving your life savings and without lots of failed prototypes and agony.
 
A squirrel size scale model wouldn’t cost much in parts and materials to fabricate.

Huge centripetal force, insane wheel flop, and getting blown off your intended line, are the primary concerns with that wheel. You can knock up the proposed and described test wheel in a matter of hours. Less if you use a bladder full of water, such as a coiled hose, instead of waiting for concrete to harden.

P.s. I know you don’t really want track geometry, but if you do and insist on fat tyres, then unless you’re extremely tall you’ll need to drop the front wheel size to 26”. Otherwise you’ve simply gone to a lot of trouble to design a rigid 29er I.e. tall, long reach, slack head angle
 
I thrive on agony.

Needs to be at least 20kW. 10kW per wheel./

Guys the rotor won't weigh that much. maybe 5kg.. No more than a scooter tire and rim and magnet ring rotor would weigh., just larger diameter.
 
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Best designs exist on the edge of possible and impossible. A 10kW 10kg wheel is not hard with cf. 15kg would be harder. I don't care if it's like riding a bull when in the cross winds. That's exciting. Requires skill.

I like the idea of a saddle pack.. 500Wh Lipo. mostly concealed right between the legs where you need it.
Has anyone given any serious thought to seatpost batteries? I remember back in the day there was a user doing a friction drive with a saddle pack lipo pack. It would be like that but bigger and more integrated into the seatpost. THe enclosure would take loads in stead of a post for the top portion at least.
 
maybe 22kW front 8kW rear. Can put the battery in the front wheel,
I've seen several kits that put the battery, motor, and controller all in the wheel like:

And:

The challenge to make the wheels light is a great challenge to have. Carbon fiber
You're talking about wheels over 50lbs each at this point with batteries, motors, and controllers. Saving a couple pounds from using carbon fiber instead of steel for the rim seems pointless.
 
I thrive on agony.

Well here's some more then..

You have massive thermal issues to deal with in this big combined wheel and you will have to derate all components massively.. or you need an amazing bespoke heatsinking.. you also need to manage the massive vibration in the battery too.

Hope to see the completed build in 2030

GaDBRkcWUAANsWy.jpg
 
Yeah moving the battery to the seatpost area would be the next best. It would be camouflaged by my thighs and easily removed for charging or swapping. 150C cells.. so 4Ah 20S pack should be fine for 30kW bursts.
 
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