24 thoughts on “Markets in everything: Reinventing the wheel….

  1. I saw this somewhere recently and saved it to evernotes. It’s really super cool. I ride my bike strictly to keep my middle-aged behind fit, so I will not be getting one. However, if I ever move somewhere where I’m not terrified of people driving the cars and I feel safe getting around on a bike, I’m getting one.

    In the meantime, I raise my glass to the innovators that make human life so much better! All of them.

    • i used to be a pretty serious bike racer.

      this looks to me like a net loser.

      the extra weight and extra friction is not all going to come back to you in boost.

      it’s a cool toy, but it seems unlikely to be a net help getting around.

        • I think it just redistributes the energy. A little harder to pedal on flat surfaces, downhill speeds reduced, but then going uphill is easier. But, I wonder if it has a plug-in charger?

          • Steve

            I think it just redistributes the energy. A little harder to pedal on flat surfaces, downhill speeds reduced, but then going uphill is easier. But, I wonder if it has a plug-in charger?

            Yes. Overall you will spend more energy riding this bike. For someone who is out of shape and can’t make it up hills without help, this might be a good deal.

          • Hit

            > rhere’s no free lunch?

            That’s right, Hit, there’s no free lunch.

            Braking energy is freely available to harvest.

            Freely available isn’t the same thing as free.

          • “Braking energy is freely available to harvest.”

            but only after the energy needed to create it was increased.

            any system like this is lossy.

            it will require a net increase in energy.

            this is simple conservation of energy.

            not created nor destroyed, just transferred and as you lose some to heat, mechanical imperfection, etc you get less out than you put in.

        • “A few pounds of extra mass is irrelevant on a bicycle.”

          as someone who used to race bikes, i can confidently say this is totally untrue.

          weight on a bike does matter, especially rotating weight.

          the difference between climbing on 1700 gr deep dish aero wheels and 1200 cram low profile climbing wheels is night and day.

          • How is rotational inertia supposed to affect climbing ability?

            > the difference between [...] 1700 gr deep dish aero wheels and 1200 cram low profile climbing wheels

            …Is located toward the outside of the wheel. Any extra rotating mass of the Copenhagen Wheel is located toward the center, reducing the rotational inertia of any extra rotating grams.

            >>> spinning weight [...] matters a lot more
            >> The batteries don’t rotate.
            > that big disc on the rear wheel does.

            Notice it takes the place of some spoke length. How much more does it mass than the spoke length it replaced? How much rotational inertia does that mass add? Considering it is concentrated toward the center of the wheel, one thing we can say for sure is that, gram for gram, it isn’t adding as much inertia as a deep dish aero wheel does, because the latter adds its extra mass toward the outside of the wheel.

          • “How is rotational inertia supposed to affect climbing ability?”

            seriously?

            because it is more difficult to impart movement.

            pedal strokes are not even. they have acceleration and deceleration. when pedals are at 3 and 9, you have very different power than when they are at 6 and 12.

            even if you were able to pedal perfect circles with absolutely even power, hills are not constant. grade increases and decreases and thus, if power is constant, speed goes up and down. every time you need to add speed, rotational inertia matters.

            even with perfectly even power on a perfectly even plane of ascent, it still take more power to get up to spreed the first time.

            ask any serious cyclist about this and they will tell you the same.

            it’s not like this is some esoteric secret.

            why do you think racers use different wheels in the alps vs in flat time trials?

            “one thing we can say for sure is that, gram for gram, it isn’t adding as much inertia as a deep dish aero wheel does, because the latter adds its extra mass toward the outside of the wheel.”

            another thing we can say for sure is it will have a great deal more than the wheel did before.

            another thing we can say for sure is that energy is conserved and that using it to generate electricity, store it, release it, and drive a motor then a wheel will result in far less motive power out than in.

            and one more thing we can say for sure is that all that extra bulk which is not in an aerodynamic configuration is going to add friction from wind which is already the biggest issue when you ride at speed.

            to claim that this device would make a ride take less energy or allow you to go overall faster is just preposterous.

          • @Morganovich

            >> How is rotational inertia supposed to affect climbing ability?”
            > it is more difficult to impart movement.

            Rotational inertia doesn’t just absorb pedaling energy. It also releases it, making it also easier “to impart movement”.

            > pedal strokes are not even.

            …Hence a flywheel helps, not hinders. If what you’re implying is true, you should be able to improve the efficiency of any car by removing its drivetrain flywheel and putting it in the trunk. Does that really sound sensible to you?

            > they have acceleration and deceleration. when pedals are at 3 and 9, you have very different power than when they are at 6 and 12.

            Greater rotational inertia helps here. Energy is absorbed by the flywheel when pedal force is the greatest, ans energy is released when pedal force is the weakest — just as in a car. This energy storage and release occurs at 100% thermal efficiency.

            > hills are not constant. grade increases and decreases

            Greater rotational inertia helps here, too. It pushes the rider up the steeper hills.

            > rotational inertia matters.

            Yes. It helps.

            > with perfectly even power on a perfectly even plane of ascent

            …Rotational inertia wouldn’t help as much.

            > it [...] take more power to get up to spreed the first time.

            Yes. This has been your only relevant point so far — in regards to hill-climbing bicycle racers. It isn’t relevant to urban bicycle commuters, however, and you haven’t shown how “this would be a killer riding uphill”.

            > ask any serious cyclist

            Why not ask a physicist or mechanical engineer?

            >>> the difference between climbing on 1700 gr deep dish aero wheels and 1200 cram low profile climbing wheels is night and day.
            > why do you think racers use different wheels in the alps vs in flat time trials?

            You already explained that aero wheels and climbing wheels trade off mass and aero. That’s a sufficient explanation, with no need to invoke rotational inertia.

            > we can say for sure [...] it will have a great deal more [rotational inertia] than [...] before.

            Please show your math. What is the threshold for “a great deal”?

            >> Braking energy is freely available to harvest.
            > energy is conserved and [...] using it to generate electricity

            …Is what all thermal power plants do. Are you claiming they don’t exist? Braking energy is thermal power. Tapping it at any non-zero efficiency — as any thermal power plant does — saves energy.

            > drive a motor then a wheel will result in far less motive power out than in.

            What is the efficiency factor between the motor and the wheel?

            > and one more thing we can say for sure is that all that extra bulk which is not in an aerodynamic configuration is going to add friction from wind which is already the biggest issue when you ride at speed.

            The biggest energy issues for urban bike commuters are drivetrain friction, rolling resistance, and braking energy.

            > all that extra bulk which is not in an aerodynamic configuration

            It looks aerodynamic. How does it affect the Cd?

            > to claim that this device would make a ride take less energy or allow you to go overall faster is just preposterous.

            Regardless, it’s true for urban bike commuters because it converts heat into useful energy without imparting a great enough mass- or drag- or rotational-inertia-penalty to make it a losing proposition.

          • Hit

            Why not ask a physicist or mechanical engineer?

            Because we might get the kind of irrelevant bullshit answers we are getting from you.

            You don’t seem to be paying attention. First, step back and admit that converting mechanical energy to electrical energy, storing it in a battery, then converting it back to mechanical energy will result in a loss compared to direct mechanical propulsion of a bicycle.

            Then, retract your nonsensical statement that a few pounds of extra mass is irrelevant on a bicycle. Even you must know that the less total weight a rider must move over a given course, the quicker they can complete the course, and as morganovich has pointed out to you, the nature of human powered bicycling is such that the rotational mass of the wheels is more important than the frame weight under most conditions – lighter being better.

            Ask yourself whether it’s reasonable to suggest that millions of bicycle riders over hundreds of years have been deluded into believing that less rotating mass is to their advantage, when in fact YOU know that a heavier wheel acting as a flywheel would improve their performance. If that were true, we might expect riders to be using wheels weighing up to one hundred pounds to improve their performance..

            Then try to understand that the flywheel on your car’s engine, if you have a standard shift, is used to regulate the rotation of the engine itself, not the speed of the car, and no, you wouldn’t be better off with it in the trunk. A car with an automatic transmission doesn’t have a separate flywheel, but uses the mass of the transmission torque converter to stabilize the rotational speed of the engine. In neither case is the flywheel intended to affect the speed of the car.

            Rotational inertia doesn’t just absorb pedaling energy. It also releases it, making it also easier “to impart movement.

            Yes, but it doesn’t provide more energy out than in, and the additional weight reduces overall performance. You are assuming that bicycle riders are most efficient when they pedal at a constant rate, and that’s not necessarily true. You might ask a bicycle rider about that.

            As morganovich wrote: “to claim that this device would make a ride take less energy or allow you to go overall faster is just preposterous.”

            You are be-clowning yourself here.

          • @Ron H.

            > converting mechanical energy to electrical energy, storing it in a battery, then converting it back to mechanical energy will result in

            …Less loss than converting kinetic energy entirely to heat, which is what happens otherwise when a bicyclist brakes.

            > retract your nonsensical statement that a few pounds of extra mass is irrelevant on a bicycle.

            A few pounds of extra mass is important when engaging in portage. When actually riding a bicycle at constant speed along a bicycle commute, it isn’t. The energy wasted by friction-braking is important. Regenerative braking is important, because it reduces this waste.

            > the nature of human powered bicycling is such that the rotational mass of the wheels is more important than the frame weight under most conditions

            …Not when climbing hills. Morganovich even explained, inadvertently, why rotational inertia helps when climbing hills.

            > a heavier wheel acting as a flywheel would improve their performance

            …Only holding total mass constant.

            >> A few pounds of extra mass is irrelevant on a bicycle.
            > If that were true, we might expect riders to be using wheels weighing up to one hundred pounds to improve their performance..

            Could they do that while holding total mass constant?

            >>> pedal strokes are not even.
            >> …Hence a flywheel helps, not hinders. If what you’re implying is true, you should be able to improve the efficiency of any car by removing its drivetrain flywheel and putting it in the trunk.
            > the flywheel on your car’s engine, if you have a standard shift, is used to regulate the rotation of the engine

            Pedal strokes = engine strokes.

            > you wouldn’t be better off with it in the trunk.

            Hence, a hill-climbing bicyclist is also better off with more rotational inertia, cet par.

            >> Rotational inertia doesn’t just absorb pedaling energy. It also releases it, making it also easier “to impart movement”.
            > the additional weight

            Rotational inertia isn’t weight. A Spinning figure skater extending arms increases rotational inertia without increasing weight.

          • 1. If you are going to respond to people’s comments by quoting them, you need to quote their entire statement in context, then respond to it in context. You contribution isn’t meaningful when you truncate others’ comments and respond to those altered statements with a different argument than you originally made.

            2. It’s obvious I’m wasting my time with you, so I’ll move on to something that interests me.

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>