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Spring-powered wheel claims to be ‘E-bike alternative at lower cost’

cyclingweekly.com

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Re: Spring-powered wheel claims to be ‘E-bike alternative at lower cost’

#21

Post by radu_floricica »

lokedhs wrote: post #13

So if I understand this correctly, it uses the downwards force on the wheel when pushing down on the pedals and converts that into rotational force on the wheel. Now, because of that annoying thing called conservation of energy, this means that you'll have to put this energy into the system by pushing down harder. I guess this translates to a feeling of sitting on a spring. That doesn't sound like very efficient peda…

I don't claim to understand the mechanics involved, but I think it's the equivalent of regenerative braking for suspensions. Instead of wasting the energy when you cross a bump, it stores it and converts it into forward motion.

Pretty smart if it's so, and depending on road conditions I actually see it as having noticeable effect. Especially considering how crazy people are about upgrading their bikes.

Re: Spring-powered wheel claims to be ‘E-bike alternative at lower cost’

#23

Post by itronitron »

Evidlo wrote: post #19

Initially I thought this was some kind of mechanical regenerative braking. I wonder if that's been attempted before. Applying the brakes would wind a spring and bring the bike to a stop. Then applying force to the pedals or manually pulling a lever would release the spring for an assisted start. Edit: Here's some mechanical regenerative braking projects: https://m.youtube.com/watch?v=yK7fyugbe6o https://m.youtube.com…

That was my expectation from the title as well. I thought it would look like an over-sized mainspring from a watch (https://en.wikipedia.org/wiki/Mainspring).

There was a small company back in the 90's or 00's that was developing very high rpm flywheels to store energy but they weren't able to work out a licensing deal with the car manufacturers.

Re: Spring-powered wheel claims to be ‘E-bike alternative at lower cost’

#24

Post by orwin »

fergie wrote: post #7

Would love to hear the opinions of some actual mechanical engineers. Can these springs really passively get you +30% efficiency? What about weight? Cyclists are obsessive about reducing rotating mass, and these wheels seem to be seriously chunky. Is this actually a thing that could work?

if this is seen in bike competition, its legit. If it is forbidden, nothing can be deduced about it and if this is allowed but not used, this is useless.

Re: Spring-powered wheel claims to be ‘E-bike alternative at lower cost’

#25

Post by duskwuff »

ivalm wrote: post #11

> The action/reaction force caused by weight compresses the springs in the upper section of the wheel and decompresses in the lower section. Using the centre as the pivot, this converts energy and reduces the frictional force in the opposite direction and facilitates the rotation. Using 10kg active weight, the mechanism is shown to generate a moment ranging from 7.3Nm to 7.8Nm.” So perpetual motion machine?

It's certainly got the sound of one. Describing the technology as "weight to energy conversion" is particularly suspect.

Re: Spring-powered wheel claims to be ‘E-bike alternative at lower cost’

#26

Post by franciscop »

This article has all the makings of a perpetual motion machine. Those are normally found by using either "springs", "magnets" or a combination of both.

There is theoretically a way to use the roughness of the terrain (so the bike going up and down as it rides) to store that energy and then use that for propulsion. When finding a rough spot, the bike trades forward momentum for a vertical impulse, so it might be possible to transform a part of this back to horizontal. I don't have a basis to calculate this, but my intuition tells me accounting for loses this energy must be very small and very difficult to capture, to the point of almost worthless. Think of a wave energy generator, but on a calm day with waves almost flat.

The article doesn't claim that though ("10kg active weight [...] generate a moment ranging from 7.3Nm to 7.8Nm"), so this is either bad reporting or a perpetual motion scam. My money is on the latter specially seeing the "infinite power assistance" label on the video, would be happy to be proven wrong though!

Fun fact: In 1775 the Royal Academy of Sciences in Paris stopped accepting proposals concerning perpetual motion.

Re: Spring-powered wheel claims to be ‘E-bike alternative at lower cost’

#27

Post by vianneychevalie »

xupybd wrote: post #9

In a closed system how can you increase efficiency without decreasing any of the energy losses. I don't get it?

You don't, you'll just end up riding on a spring-y bike and put energy into the system by pushing on the pedals a bit further than usual relative to the ground.

Re: Spring-powered wheel claims to be ‘E-bike alternative at lower cost’

#28

Post by wiredfool »

fergie wrote: post #7

Would love to hear the opinions of some actual mechanical engineers. Can these springs really passively get you +30% efficiency? What about weight? Cyclists are obsessive about reducing rotating mass, and these wheels seem to be seriously chunky. Is this actually a thing that could work?

No. There’s no 30% gain to be had. Losses in a properly maintained bicycle are already far lower than this.

Re: Spring-powered wheel claims to be ‘E-bike alternative at lower cost’

#29

Post by C19is20 »

itronitron wrote: post #17

>> "We have requested a SuperWheel to test and will report back." I look forward to reading that. Cycling magazines usually do a fairly rigorous evaluation of new tech in their articles.

...*used to be "obsessive about rotating mass".

GCN: https://youtu.be/0QDnUkUaQfk

See also YouTubers Hambini, Peak Torque and Durianrider (on a tech day) for more cycling debunkness.

Also, amongst others, it'll be a real pain if YT's ad policy drives these guys away. Well, not for the cycling industry, and associated lapdog journo's.

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