I saw bike cops last year on the popular multiuse path I ride on frequently. I thought this might be some sort of new patrolling effort, but I noticed they were from the Berkeley police department, two towns over (out of their jurisdiction). It turns out, I believe, they were just commuting to work like everyone else (they do bike patrolling around town, but for normal police work, not cracking down on ebikes).
What a dumb looking bike
- Thread starter harrisonpatm
- Start date
marvin78
10 kW
Nice insight in how they built this contraption.
If you want the parts, he's offering them for free
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While I didn't watch the review video, since this one was about the insides, I did watch it...and this thing is even more terrible than I thought it would be. :/
Each "reveal" of a part made my brain go "why would you do that?" again and again....
I'm not an engineer by any means. At best I'm an awful hack version of Macgyver. Buuuut...I am certain I could come up with a better way to do what they did. (I don't have the time to waste on it since it would never be built, but...yeah, I'm sure I could).
Some things would still not work as well as the more typical versions do, like the wheels. I'd have to research magnetic bearings to see if there is a good reliable way to "float" the wheel on them to greatly reduce friction; I can't think of another way to do the wheels the way they did them without far more friction than they should have.
I can imagine a way or two to only support it at the clamp area, and have bearings only there, but taht would have to be a very stiff frame and clamp and wheel to avoid wobbliness. I'm sure I couldn't actually build such a thing. (there was once I time long long ago that I wanted to build a hubless wheel bike for the visual-strikingness of it, but the complications of design and building it kept me from doing more than sketching things on paper...but I did do a bit of research at the time to see what might be done).
Each "reveal" of a part made my brain go "why would you do that?" again and again....
I'm not an engineer by any means. At best I'm an awful hack version of Macgyver. Buuuut...I am certain I could come up with a better way to do what they did. (I don't have the time to waste on it since it would never be built, but...yeah, I'm sure I could).
Some things would still not work as well as the more typical versions do, like the wheels. I'd have to research magnetic bearings to see if there is a good reliable way to "float" the wheel on them to greatly reduce friction; I can't think of another way to do the wheels the way they did them without far more friction than they should have.
I can imagine a way or two to only support it at the clamp area, and have bearings only there, but taht would have to be a very stiff frame and clamp and wheel to avoid wobbliness. I'm sure I couldn't actually build such a thing. (there was once I time long long ago that I wanted to build a hubless wheel bike for the visual-strikingness of it, but the complications of design and building it kept me from doing more than sketching things on paper...but I did do a bit of research at the time to see what might be done).
marvin78
10 kW
But there you go already, if the wheel needs to be super stiff / rigid, ride quality is already worse then a normal hub with spokes.
You could probably fix the friction issue with magnetic bearings ( though I'm not sure how that would work, I can't imagine permanent magnets being strong enough to levitate the weight of that entire bike ( depending on riding/braking conditions )) but you're still stuck with a worse ride quality for an ebike.
E-motorcycle could probably work much easier with hubless wheels, there are motorcycles without hubs and I imagine it's because they have enough power to offset the added friction ( and already have rigid wheels to start with ).
The whole notion of a hubless ebike seems just a combination of idea's which just shouldn't be combined.
You could probably fix the friction issue with magnetic bearings ( though I'm not sure how that would work, I can't imagine permanent magnets being strong enough to levitate the weight of that entire bike ( depending on riding/braking conditions )) but you're still stuck with a worse ride quality for an ebike.
E-motorcycle could probably work much easier with hubless wheels, there are motorcycles without hubs and I imagine it's because they have enough power to offset the added friction ( and already have rigid wheels to start with ).
The whole notion of a hubless ebike seems just a combination of idea's which just shouldn't be combined.
I think magnetic bearings are not a solution for such case, and it's not true that they're frictionless in general. There is an electromagnetic friction (eddy currents) that result in some motion energy converting to waste heat. I dont know how this compares to ball bearings.
marvin78
10 kW
Not to mention you would need to power the circuit from your battery... bye bye range. Permanent magnets can't be used in high performance bearings because they are not stable, you need switching magnets which can require a lot power depending on weight and acceleration/decelarion forces they need to counter.
I don't see that happening on an ebike.
Sealed hydronamic bearings with magnetic fluid seals using ferrofluid oil, because the entire inside rim is a bearing surface. With neodymium magnets along the rim to make sure there is no leak. Or simpler, sealed fluid bearing with labyrint seal. Or best, combination of the two ( magnetic + labyrint seal with ferrofluid, to make sure no fluid loss will occur lowering maintenance requirements ).
I don't see that happening on an ebike.
Sealed hydronamic bearings with magnetic fluid seals using ferrofluid oil, because the entire inside rim is a bearing surface. With neodymium magnets along the rim to make sure there is no leak. Or simpler, sealed fluid bearing with labyrint seal. Or best, combination of the two ( magnetic + labyrint seal with ferrofluid, to make sure no fluid loss will occur lowering maintenance requirements ).
marvin78
10 kW
Uh oh... Sam got his hands on one lol taking this on mtb trails
edit: it actually held up far better then I initially expected... even if it was unridable ( ... wait wasn't it already from the start ) at the end.
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Chalo
100 TW
That is the treatment that bike deserves.
DanGT86
100 kW
this part where he is carrying Lewi in the wheel is amazing.
I guess it's a plus when the body you run over can't get caught in your spokes and crash you....but a minus that you have to drag it along and get caught with it. 
marvin78
10 kW
I would be scared shitless he would take a turn to tight and I'd hit my head on the pavement or something...
MylarStar
100 mW
Oh ha ha yeah I watched that video too. It sounds like a rock tumbler.
