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  1. #1
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    What do I need for self-generated charging of all gadgets?

    I'm trying to be completely self-sufficient in my approach to biking. That means using my legs to generate not only motion, but all the juice needed to power lights, computer, GPS, radio, cellphone, laptop or tablet, and anything else I might add down the line. I'm looking at either a Shimano DH-3N71, SON20 or SON28 hub generator, lithium-ion battery (to be determined), Dinotte XML-3 headlight and Daytime Red taillight. Ideally, I'd have everything hard-wired to draw whatever current is needed from the battery, but if I have to use the intermediate step of recharging the device batteries from the master battery (or skipping the master battery altogether and charging everything off the hub generator as needed), I'd be okay with that. If I could also use the hub generator to recharge spare batteries for the various devices and swap them out as needed, that would be okay, too, but I'd rather not have to mess with popping batteries in and out all the time, much less carrying and keeping track of the spares.

    I'm not that electronically inclined. I do realize that everything needs to be the same voltage, or else I'll have to step up or step down the voltage to a particular device. I also know I don't want to overcharge the battery or batteries, either the li-ion or the device batteries, so I'd need to incorporate a meter and/or shutoff circuit. I'd envision something that would automatically kick in to charge the battery when it's low and kick out when it's fully charged, but if I have to do that manually with a toggle switch when the meter reads low or high, that's acceptable.

    So what do I need to do to accomplish this? Anything I'm overlooking?
    I'll think of something clever to put here later...

  2. #2
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    I don't know the answers to all of your questions, but it would be nice to have one of these:


    http://www.en.tout-terrain.de/access...-power-supply/
    Chaad--'95 DeKerf Team SL, '02 Lemond Buenos Aires, '05 Novara Buzz, '73 Schwinn Collegiate, '06 Mountain Cycle Rumble, '09 Dahon Mariner D7, '12 Mercier Nano, '12 Breezer Venturi

  3. #3
    Senior Member Bluechip's Avatar
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    Or you could get the Luxos U headlight with usb charger for about the same price.

    I am using the SP PD8 dynamo hub. So far so good.
    Last edited by Bluechip; 06-26-13 at 11:00 AM.

  4. #4
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    Quote Originally Posted by chaadster View Post
    I don't know the answers to all of your questions, but it would be nice to have one of these:


    http://www.en.tout-terrain.de/access...-power-supply/
    Thanks, that may be part of the answer. Their website lists Peter White Cycles as a distributor, though I didn't immediately find it on their website.
    I'll think of something clever to put here later...

  5. #5
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    Quote Originally Posted by Bluechip View Post
    Or you could get the Luxos U headlight with usb charger for about the same price.
    Also a possibility. Thanks!
    I'll think of something clever to put here later...

  6. #6
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    "I'm trying to be completely self-sufficient in my approach to biking. That means using my legs to generate not only motion, but all the juice needed to power lights, computer, GPS, radio, cellphone, laptop or tablet, and anything else I might add down the line."

    You can definitely some something to power some of this stuff, but if you expect to be able to power all of it - if I understand you correctly - you are just being unrealistic.

    As someone else mentioned, you can get a
    Luxos U headlight with usb charger. This will power the front light when you need it, or while the front light is not on it will provide usb power to charge 1 other device.

    But that's as much power as you're going to get out of it. Anything that doesn't have a usb charger is going to be difficult if not impossible to charge (I don't know if it can be done or not). And anything that does get charged via usb, you'll only be able to charge 1 thing at a time.

    I don't know if there are other options, but a regular dynamo hub generator just doesn't put out that much power. It's plenty of power to charge a cell phone (and you can use the gps on your cell phone as your gps). I don't think it's actually enough power to charge a tablet. It's really not enough power to charge a battery for a light like the Dinotte XML-3, or an actual laptop.

    Are you looking for something you could ride your bike at night on to produce power? I just think you're being overoptimistic about how much power you can produce on a bike...

  7. #7
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    P.S. From Peter White -
    "The Luxos U won't charge a car battery, or an iPad, though it will charge an iPhone or a Garmin Edge 810. The larger battery in the iPad needs too much current; more than the Luxos U can provide. If you need to charge an iPad on the road, you'll need to find another solution. Hub dynamos just don't have enough power output."

    http://www.peterwhitecycles.com/b&m-hl.asp

    It's not specific to the Luxos U either - any dynamo is just not going to provide that much power...

  8. #8
    Senior Member 01 CAt Man Do's Avatar
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    I don't have a lot of experience with Dynamos but agree with Paul that the power put out by a single dynamo is limited. Items like a laptop or DiNotte Daytime Rear light are going to draw humongous amounts of power. Trying to charge them from a Dynamo would be a major ordeal. Even if you incorporated a second dynamo it would be a stretch.

    A better option might be to carry a rather good size Li-po battery ( for back-up ) and carry a compact fast-charger along to charge it (when you find a spot to charge it.). You could make a game of it. Find the spot to draw free power "from the man". You got to stop and eat somewhere, might as well be a place that has electrical outlets. This not an idea you should shrug off. More and more I'm seeing electrical outlets for the hybrid cars at certain shopping centers. Li-po batteries can handle a pretty fast charge. I can't guarantee how well it would work but it is an idea worth looking into.

    Anyway, incorporate both dynamo and fast-charging back-up battery ideas and you might get something that at least comes close to meeting your needs.

  9. #9
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    I think my kindle fire sneers at the normal usb current of 500mA max. Seems like I had trouble charging an iPad with an iPod charger. Not sure why they need so much current to charge, I would think they could just charge slower.

    Backing up what was said above, most dynohubs nowadays are limited to around 500mA, so I'm guessing those larger devices aren't going to be happy charging from that.

  10. #10
    Zoom zoom zoom zoom bonk znomit's Avatar
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    My iPad mini tells me its not charging off most of my chargers, but in the morning magically the battery is full.
    Last edited by znomit; 06-27-13 at 01:39 AM. Reason: spelling

  11. #11
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    Okay, charging a laptop might be beyond my ability, and I might need 2 or even 3 (I have a trike) hub generators to take care of everything else. I don't plan on biking after dark, so could use a headlight that I only flash on for a moment to make myself visible to oncoming traffic, if necessary, otherwise won't have a headlight drawing current. Little things like the computer should be relatively insignificant, and I don't have to be charging everything at once. I still need to find out what's required for transformers or whatever. Anyone have any experience with using a hub generator to power lights (or anything else) that are normally battery powered? And, sure, I can always find an outlet to bum some juice, but it's more of a philosophical green tree-hugging thing.
    I'll think of something clever to put here later...

  12. #12
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    Quote Originally Posted by SecondChildhood View Post
    Okay, charging a laptop might be beyond my ability, and I might need 2 or even 3 (I have a trike) hub generators to take care of everything else. I don't plan on biking after dark, so could use a headlight that I only flash on for a moment to make myself visible to oncoming traffic, if necessary, otherwise won't have a headlight drawing current. Little things like the computer should be relatively insignificant, and I don't have to be charging everything at once. I still need to find out what's required for transformers or whatever. Anyone have any experience with using a hub generator to power lights (or anything else) that are normally battery powered? And, sure, I can always find an outlet to bum some juice, but it's more of a philosophical green tree-hugging thing.
    If you're planning a long trip, I would still recommend the Luxos U - someone else mentioned that it's the same cost as a separate charger anyways, and it would give you a backup light if you accidentally need to bike at night after all.

    I'm a tiny bit confused by saying laptop and "computer" - maybe you mean a speedometer? I mean a wired speedometer doesn't really need anything to charge it, the tiny battery in there will last for years and years without needing to be replaced. (And I don't know of any you can recharge anyways.)

    I mean you get a very nice light -


    That runs off of a dynamo and you also get a charger via the dynamo at the same time. This is as efficient as you're going to get for your headlight.

    If you could keep most everything else on your cell phone (gps is definitely something you don't need separate if you have a smartphone) you could just leave your cell phone plugged into the usb charger most of the time...

  13. #13
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    Quote Originally Posted by PaulRivers View Post
    If you're planning a long trip, I would still recommend the Luxos U - someone else mentioned that it's the same cost as a separate charger anyways, and it would give you a backup light if you accidentally need to bike at night after all.

    I'm a tiny bit confused by saying laptop and "computer" - maybe you mean a speedometer? I mean a wired speedometer doesn't really need anything to charge it, the tiny battery in there will last for years and years without needing to be replaced. (And I don't know of any you can recharge anyways.)

    I mean you get a very nice light

    That runs off of a dynamo and you also get a charger via the dynamo at the same time. This is as efficient as you're going to get for your headlight.

    If you could keep most everything else on your cell phone (gps is definitely something you don't need separate if you have a smartphone) you could just leave your cell phone plugged into the usb charger most of the time...
    I have touring in mind, and thanks to yours and others' comments, I think the Luxos U is the way to go for a headlight and USB for the cellphone and anything else I can charge with USB. By "computer" I mean what you refer to as speedometer, a Planet Bike Protégé 9.0 Cyclocomputer (at least for now). Yes, it does take a battery that lasts for years, but the point is not to use any outside juice at all. I may have to compromise on that point.
    Thanks, everybody, for your comments so far!
    I'll think of something clever to put here later...

  14. #14
    Senior Member Looigi's Avatar
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    Realize that your legs are do not create the energy to charge your devices, they will only be converting energy from food you eat into charged batteries. Leg power is only about 25% efficient in converting consumed calories into power. Then there will be additional loss in the generating of electrical power and charging of the batteries. The growing, transport, storage, and processing of food has a significant environmental impact, so charging your devices with leg power is not without it's environmental cost.

  15. #15
    Senior Member Rob_E's Avatar
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    Quote Originally Posted by Looigi View Post
    Realize that your legs are do not create the energy to charge your devices, they will only be converting energy from food you eat into charged batteries. Leg power is only about 25% efficient in converting consumed calories into power. Then there will be additional loss in the generating of electrical power and charging of the batteries. The growing, transport, storage, and processing of food has a significant environmental impact, so charging your devices with leg power is not without it's environmental cost.
    I find very little difference in exertion when using or not using a dynamo. So while pedal-power may be inefficient overall, I would be surprised if there was a significant increase in food intake if you were already pedaling. Some days I ride a bike with a generator hub, and some days I ride another bike. I have not noticed myself eating more on the dynamo days.

    To the OP: I think that in general, and using the supplied suggestions in particular, the way to solve all your various voltage problems is to go fully USB. USB works for many phones. Tablets may draw more power than the hub puts out when in use, but they may charge as long as the tablet is off or sleeping when charging. My plan is to use an external battery pack that is charged via USB, charge that up over the course of the day, and use that to charge my tablet and phone.

    Using dynamo-powered headlights eliminates the need to try and power battery-powered lights. The Luxos U does seem ideal for what you want, and it's the device I've been lusting after. There are also USB-powered battery chargers, so if you had one of those and a couple of rechargeable AAs or AAAs, you might be able to supply all of your energy needs from one hub. Except a laptop. If you had a very efficient laptop that you used very seldom, and way to recharge it via USB, then maybe. And your speedometer still creates a problem. I don't know if you can get a rechargeable battery of the size usually used in a cycle computer, and if you could, it seems like it would be a lot of effort and expense to be able to say that you're completely self-powered. Like Looigi's point, the effort you put into not having that one, non-rechargeable battery probably exceeds the benefits of converting it to pedal power. Better you should see if there's a rechargeable cycle computer, or one that runs on AAAs, or just use your phone as the speedometer.

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    Quote Originally Posted by SecondChildhood View Post
    I have touring in mind, and thanks to yours and others' comments, I think the Luxos U is the way to go for a headlight and USB for the cellphone and anything else I can charge with USB. By "computer" I mean what you refer to as speedometer, a Planet Bike Protégé 9.0 Cyclocomputer (at least for now). Yes, it does take a battery that lasts for years, but the point is not to use any outside juice at all. I may have to compromise on that point.
    Thanks, everybody, for your comments so far!
    Hey, yeah, while I haven't really done the research on it (whereas I have done a ton of dynamo light research), I've never seen a bike speedometer that's rechargeable. They all take batteries, and they always seem to take those watch batteries which as far as I know have no rechargeable options. The best I know of for a separate speedometer is a wired version - wireless speedometers need a new battery every year or two, wired versions last for years.

    My only other suggestion is that there are smart phones apps that will do the functions of a speedometer via it's gps, and since you could recharge it via the dynamo hub, that might technically meet your needs. :-)

  17. #17
    Senior Member 01 CAt Man Do's Avatar
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    Quote Originally Posted by SecondChildhood View Post
    I have touring in mind, and thanks to yours and others' comments, I think the Luxos U is the way to go for a headlight and USB for the cellphone and anything else I can charge with USB. By "computer" I mean what you refer to as speedometer, a Planet Bike Protégé 9.0 Cyclocomputer (at least for now). Yes, it does take a battery that lasts for years, but the point is not to use any outside juice at all. I may have to compromise on that point.
    Thanks, everybody, for your comments so far!
    To help us help you we really need a little more info on what kind of touring you are planning. Hard to recommend things when you really don't know what situations you will be dealing with. What I would consider doing during a tour might not be what someone else might do and vise versa.

    Touring ( which I've never done before per say ) would mean making sacrifices. That would be hard enough as I see it without putting in the limitation of being overly green-minded. I figure it's enough to worry about how much food and water you have, whither you know where you are going to sleep next, what weather is coming down the pike..etc, etc. Many things to worry about on an unsupported tour. I figure it's better to have options. The more the better. If that means plugging into an electrical outlet somewhere along the way I'd consider doing that if it means more peace of mind. Now if you can limit your use of electrical devices to just minutes a day then the possibility of having everything charge off of a dynamo becomes more possible.

    Things I might consider doing to help with electronic devices. : I would consider buying a good dynamo/ lamp. I doubt I would do much riding at night on a tour but things happen. I would use at least one USB/self-contain rear light and one rear light that uses standard AA's. Standard AA or triple A's you can buy almost anywhere. To help power the smart phone I would purchase a couple extra external ( USB )rechargeable batteries. I would then let one of the spare batteries charge all day on a solar charger and see how that works. The other battery would be supporting my smart phone/ GPS so I wouldn't have to worry about the internal battery fading after riding all day. Personally If I were doing the tour I figure I'd sleep in a hotel at least every four of five days just so I could get the stink off of me. I could also charge everything up to full capacity and be set for the next couple days ( good Lord willing and the creek don't rise )

  18. #18
    Rod & Judy gracehowler's Avatar
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    If you haven't read it, Wayne Estes has a great article about solar self contained touring on CGOAB;
    http://www.crazyguyonabike.com/doc/?...c_id=9258&v=tG
    R&J

  19. #19
    Senior Member 01 CAt Man Do's Avatar
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    Quote Originally Posted by gracehowler View Post
    If you haven't read it, Wayne Estes has a great article about solar self contained touring on CGOAB;
    http://www.crazyguyonabike.com/doc/?...c_id=9258&v=tG
    R&J
    Grace I want to thank you for your post. I'm going to bookmark this guys blog because it contains a wealth of knowledge having to do with self-sufficient electronic use.

    Secondchildhood...You want to take some time and read what this guy has to say about self-sufficient touring. While he starts off with solar panel use he continues on with dynamo use a good way down the page. Of real interest to me is the Sunup Eco DS-1R ( non-hub ) ( no-drag ) dynamo that he mentions that puts out about 8watts of power. The man talks about almost every type of battery charger there is. This is a "must read" if you are serious about S-Sufficient electronic use. ( I didn't read the whole blog but plan to when I get more time ).

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    The answer to the OP's question is a nuclear power plant.

    He really should explain why he wants to be independent and why he needs to carry so much crap.

    What he wants to do doesn't make a whole lot of sense.
    Last edited by njkayaker; 06-28-13 at 05:30 PM.

  21. #21
    Riding like its 1990 thenomad's Avatar
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    Quote Originally Posted by njkayaker View Post
    The answer to the OP's question is a nuclear power plant.

    He really should explain why he wants to be independent and why he needs to carry so much crap.

    What he wants to do doesn't make a whole lot of sense.
    Now I know this will come off sounding snarky but I really do think its a relevant issue. You want to be energy independent for green reasons yet are willing to spend a lot of money on special devices to do it. There are resources mined, refined, processed and manufactured in order to make each of these gadgets. In essence, your carbon footprint grows larger in your technological solutoons to reduce your carbon footprint. Id equate it to a single person buying an electric car to be "environmental" to offset the impact of the other car. The greenest way to reduce impact is to use equipment already manufactured / reuse/recycle. ride vintage bikes, use vintage equipment as much as posible, use paper road maps, the same rechargeable batteries, perhaps one smart phone (older model that would have hit the landfill?) Or none at all. Bottle generators work, not great but it prevents more waste. That seems more green and "off the grid" to me.
    My blog about rides, bikes and builds: ridesgoneby.blogspot.com

  22. #22
    Senior Member 01 CAt Man Do's Avatar
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    Quote Originally Posted by thenomad View Post
    Now I know this will come off sounding snarky but I really do think its a relevant issue. You want to be energy independent for green reasons yet are willing to spend a lot of money on special devices to do it. There are resources mined, refined, processed and manufactured in order to make each of these gadgets. In essence, your carbon footprint grows larger in your technological solutoons to reduce your carbon footprint. Id equate it to a single person buying an electric car to be "environmental" to offset the impact of the other car. The greenest way to reduce impact is to use equipment already manufactured / reuse/recycle. ride vintage bikes, use vintage equipment as much as posible, use paper road maps, the same rechargeable batteries, perhaps one smart phone (older model that would have hit the landfill?) Or none at all. Bottle generators work, not great but it prevents more waste. That seems more green and "off the grid" to me.
    Hey, if someone wants to be self-sufficient during a bike tour it makes perfect sense. If you own lights, cameras, phones, GPS unit, tablet or lap top...whatever, you want to be able to use these things during your trip without the inconvenience of having to find an electrical outlet. Hey, I don't own a tablet but if I did I would love to bring it on a tour as it would add to my enjoyment of my time off the bike.

    To me, being "Green" really has nothing to do with it. All that carbon footprint stuff is a bunch of nonsense anyway because unless everyone on the planet is willing to give up every modern convenience manufactured with petroleum products ( almost everything is manufactured with petroleum products ) the planet is still going to hell in a hand-basket. A couple hundred years here or there isn't really going to make a big difference. Eventually we will run out of the natural resources needed to maintain modern infrastructure and when that happens no one will give a damn about "carbon footprints". All people will care about is where to get clean water and food. Everything else will be considered non-necessities. Yeah, I paint a bleak picture of the future. Sorry about that, I hate being the buzz killer. Wish I could be more hopeful but the events of past human history have a way of repeating themselves.

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    Senior Member Looigi's Avatar
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    Quote Originally Posted by Rob_E View Post
    I find very little difference in exertion when using or not using a dynamo. So while pedal-power may be inefficient overall, I would be surprised if there was a significant increase in food intake if you were already pedaling. Some days I ride a bike with a generator hub, and some days I ride another bike. I have not noticed myself eating more on the dynamo days.....
    Conservation of energy, it's the law. Energy in, energy out, and energy stored in your body. It's all accountable. You can calculate what you need to eat in order to charge those batteries. If you didn't eat it today, you will eat it tomorrow, or you ate it days ago. It aint free.

    Think about riding in general. If you ride a decent clip, you burn 500-600 calories per hour. What does that cost? A couple of energy bars (or a Big Mac) might cost ~$3.50. So the cost is not much different than driving and SUV an equivalent distance. And what about the environmental impact? I'm sure driving the SUV is worse, but there is significant environmental impact in producing, packaging, transporting and metabolizing those energy bars. It aint free.
    Last edited by Looigi; 06-29-13 at 06:36 AM.

  24. #24
    Senior Member Looigi's Avatar
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    oops
    Last edited by Looigi; 06-29-13 at 06:34 AM.

  25. #25
    Senior Member Rob_E's Avatar
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    [QUOTE=Looigi;15795723]Conservation of energy, it's the law. Energy in, energy out, and energy stored in your body. It's all accountable. You can calculate what you need to eat in order to charge those batteries. If you didn't eat it today, you will eat it tomorrow, or you ate it days ago. It aint free./QUOTE]

    No one's trying to break he laws of physics, but we are not dealing with a closed system nor, as you already pointed out, a particularly efficient one. Most of us don't eat the exact amount of food needed to keep us going, and not every bit of exertion on a bike translates directly into forward motion. You can try to calculate the exact amount of food required to generate a specific amount of energy with a dynamo hub, but it will be a number that varies widely from person to person. It will also, I expect, be a very small number if you factor in the assumption that the person would be on the bike, pedaling, in both situations with he only difference being whether or not your using a generator to recapture some of the expended energy.

    Quote Originally Posted by Looigi View Post
    Think about riding in general. If you ride a decent clip, you burn 500-600 calories per hour. What does that cost? A couple of energy bars (or a Big Mac) might cost ~$3.50. So the cost is not much different than driving and SUV an equivalent distance. And what about the environmental impact? I'm sure driving the SUV is worse, but there is significant environmental impact in producing, packaging, transporting and metabolizing those energy bars. It aint free.
    You're all over the map. Are you talking about physics or economics? From a physics standpoint, the energy requirements to move an SUV a fixed distance far exceed the requirements to move the comparatively much smaller cyclist the same distance. From a money standpoint, the example is very simplistic and ignores many variables while throwing out some arbitrary assumptions on the source/cost of food energy and the energy expended. Yes, you need to eat if you're going to bike, but you need to eat even if you don't bike. Otherwise the drivethru at McDonalds would be tailor made for bikes, getting there Big Macs to refuel. But it turns out that people in SUVs eat Big Macs, too. But the economics of riding a bike vs. driving are not what's at issue here. In fact, being that this is this is the electronics forum, the main thing at issue is how can the OP use a bike to charge stuff. Because the stated reason is environmental, we can certainly hypothesize about whether energy produced on the bike will be more or less environmentally friendly than energy from other sources, but that's not a strict, conservation of energy, physics question, nor is it a straightforward economic one. It's an interesting question, and one I'd love to see answered, but it's complicated. You would need to figure the exact, extra, food requirements to generate that extra energy and the environmental impact of that food compared to the environmental impact of producing that energy at the power plant. Some rather large variables might be he cyclist's fitness and metabolism, the type of food being eaten, and the way the local power company generates energy. It's not a simple physics puzzle. And in real world numbers, I expect it will be very difficult to calculate because I can barely feel a difference in riding when I turn on my generator hub, and I can see no difference in the amount of food I eat.

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