Interesting design concept

KirstinS

Esteemed Pedelecer
Apr 5, 2011
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Brighton
at least thats what I thought when i saw this Velocity e-bike features weight-reducing removable power system - Images

I'd be interested to hear from those engineers and other knowledgable folk on here what you think of it.

IF shaft drive bikes are rather inefficient then wouldn't that apply here to ? Other pitfalls that occur to me battery size and cooling. Not to mention cost and reliability of complex components. I'm not really sure if the pedals themselves would be driven - which doesnt seem like a great idea. Still I kind of like the concept as it looks neat and could lead to having a very balanced bike as all the weight is central
 

indalo

Banned
Sep 13, 2009
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Herts & Spain
While I suppose these chaps who spend lots of time and energy trying to re-invent the wheel, so to speak, are to be applauded, I think this attempt like many others before, will never see the light of day as a mass production vehicle.

The committees who judge competitions for work such as this bike really amaze me. This got a gold medal which causes me to wonder what the silver and bronze efforts were. The bike is a mixture of art and engineering but I think it fails on both counts but I'm a Philistine when it comes to the arts so others may feel differently.

Indalo
 

KirstinS

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Apr 5, 2011
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Brighton
While I suppose these chaps who spend lots of time and energy trying to re-invent the wheel, so to speak, are to be applauded, I think this attempt like many others before, will never see the light of day as a mass production vehicle.

The committees who judge competitions for work such as this bike really amaze me. This got a gold medal which causes me to wonder what the silver and bronze efforts were. The bike is a mixture of art and engineering but I think it fails on both counts but I'm a Philistine when it comes to the arts so others may feel differently.

Indalo

Fair enough Indalo but I just wondered why you feel that way- not on the art point as this is purely subjective but on the engineering. The pitfalls I point out dont seem insurmountable (I'm not even sure they are valid as I'm no enginneer)

So, I guess I'm after some input from an engineering perspective rather than either aesthetic or marketing
 

danfoto

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Dec 2, 2010
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If the rear end is in fact rigid (in the sense of doesn't have suspension), that frame design is a joke from an engineering POV.
 

KirstinS

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Apr 5, 2011
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If the rear end is in fact rigid (in the sense of doesn't have suspension), that frame design is a joke from an engineering POV.
yes, i did wonder about that, particularly as there is no need whatsoever for it. Just as easily have a more standard, trianglualr hardtail design

So lets say we stick that into the design

Anyone able to comment on the drive concept itself ?
 

themutiny

Esteemed Pedelecer
Feb 26, 2009
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Or

Buy a Cytronex and a normal wheel. Swap them in 30 secs. Don't mount bottle battery.
Platinum design winner? :rolleyes:
 

NRG

Esteemed Pedelecer
Oct 6, 2009
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Yes cant see how the frame would ever be rigid enough or strong enough...the idea of a removable power and battery unit is neat though...although the bevel type drive through the crank is inefficient and tend not to be very powerful like the Gruber assist idea....at least the Gruber is retrofittable to other bikes and a lot lighter even if its not removable.....
 
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flecc

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Oct 25, 2006
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That's even weaker, apart from the dodgy frame and front fork, the wheels won't last long on UK roads.
 

mike killay

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Feb 17, 2011
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The problem for the rear end to be strong enough is the need for massive amounts of steel, and thus a weight penalty. This concept is frankly ridiculous, it flies in the face of long established engineering principles regarding space frames and for what?
A triumph of design over practicability.
As to the engine etc being removeable, again, why?
The theory is laudable, but how many people want to remove their engines for the week end? I suspect that the few who do would prefer a second, proper racing etc. bike.
 

danfoto

Esteemed Pedelecer
Dec 2, 2010
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Sarfeast England
But for those that don’t understand how that rear end on the Velocity can be strong enough, his anytime folder will blow your mind.
Er ... no. It just proved to me that he's a designer, not an engineer.
 

flecc

Member
Oct 25, 2006
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But that makes no sense. Taking the two rear upper struts up to the seat tube would be both stronger and allow less material to be used and weight saved.

Designs like this are style over function.