Gene'sG

Good question! I'm sure you could leave the resistance unit in place, but would need to find a way to connect the generator motor. That could get complicated, you'd probably need a custom adapter. As long as there is enough distance between the motor and the resistance unit, there shouldn't be much interference. If you're looking for a setup that allows you to generate electricity, and still be able to add resistance, check out my other 'able using a spin bike: https://www.instructables.com/id/Spin-Bike-RC-Motor-Pedal-Generator/ That design allows for both, and benefits from a much bigger flywheel!

Thank you, and nice work! I considered using an old drill for this project too, but you are right - really noisy. Using the RC motor is much quieter for 2 reasons: (1) there are no gears (2) there are no brushes. If you watch the videos, you can easily hear me talking while I'm demonstrating the generator - it is fairly quiet to operate.As far as voltage regulators go, it's a good option if you are charging/powering devices that are sensitive to higher voltage, or you want to put a specific voltage into a device/battery, or you just don't want to watch the meter. I like this regulator, however if you need up increase (step up) the voltage like in your case, this one should do the trick.

Hi uWave - what you are proposing makes a lot of sense. When I initially set out on this journey of building pedal generators, my intent was to make a product or products I could sell. Those dreams were squashed by the accounting department (wife) and the scheduling department (also wife) so with limited time and funds I decided to just give away my designs - and here we are. I make a few dollars a month by people following my links to Amazon, so I guess that's something for my time. In my first design https://www.genesgreenmachine.com/build-spin-bike-pedal-generator/, I did add a charge controller which works perfectly for powering anything 12v (up you the limit of you and/or the charge controller). Creating a purpose build PCB with a controller that gives both 12v and USB 5v outpu...

Hi uWave - what you are proposing makes a lot of sense. When I initially set out on this journey of building pedal generators, my intent was to make a product or products I could sell. Those dreams were squashed by the accounting department (wife) and the scheduling department (also wife) so with limited time and funds I decided to just give away my designs - and here we are. I make a few dollars a month by people following my links to Amazon, so I guess that's something for my time. In my first design https://www.genesgreenmachine.com/build-spin-bike-pedal-generator/, I did add a charge controller which works perfectly for powering anything 12v (up you the limit of you and/or the charge controller). Creating a purpose build PCB with a controller that gives both 12v and USB 5v output, along with a meter in a nice box that can be mounted on handlebars was actually part of my "grand plan" design. Meter should show amps, watts, volts, total watt hours and total time (along with a reset button). Also adding in bluetooth LE output for watts generated for the Zwift users out there was another feature that I'd include. You'd probably sell the heck out of that. Happy to collaborate with you on the design if you'd like my guidance.

So thrilled to hear you built it - please share a picture of your build! The challenge when you get up in watts drawn is we humans aren't creating steady power - it's very difficult to keep the pedals cranking at exactly the same speed/power. You've also hit on the solution by adding the super capacitor. The other option is to drop in a 12v lead acid battery to the circuit, which is the approach I have personally taken. Adding the battery works as a buffer of our varying input (likewise with the ultra-capacitor), smoothing out the voltage input to the inverter.

Hi alcurb - if you're looking for an easy build "bike generator->TV", I've put together an -ible you might want to check out:https://www.instructables.com/id/Best-DIY-Bike-Trainer-Generator/

As cool as it might, be - I’m never going to be able to produce 2400 watts with these legs (show me a human that can). By the way, the motor I use has more capability than I’ll ever push - it’s max rating is 1820 watts, so the limiting factor on watts produced will be the person spinning the cranks on the bike. I’ve personally generated almost 400 watts with this setup (and I’m an old, out of shape, fair weather mountain biker), I’m sure others can do much better.

Very cool - sounds like it would work much better than your standard fair duct tape, I might have to get some! Looks like you can find it on Amazon too: https://amzn.to/2Gu9JM0

I’ve used MakeXYZ before with good luck. https://www.makexyz.com/

Thanks rrwood! Don't believe for a second I haven't thought about coming up with some kind of Zwift integration. Just haven't figured out all the details yet...

Hi Garzo - I agree with the idea of a smart charger, I use the same for charging a Lipo battery. However, I've avoided using a step down regulator by designing this to produce power within the voltage range that is suitable for using car chargers and inverters. The regulator would add another area of power loss, and efficiency was one of my goals. You certainly could add a regulator if you really need fine control of voltage, but isn't necessary for charging/powering as I demonstrate.

Hi Simon, to help answer this question, I created another video and added it under the "Charge!" section. If your question isn't answered after watching that video, I'll be happy to clarify.

Thanks, WeavingBird! As much as I sweat, I really need the fan :)

Hi Gordon - thank you! It really is an easy build, the hardest part is drilling the two holes in the metal plate in the right place. I like the flywheel on this design, which makes for smoother pedaling than on the bike trainer version I did last year.

Good question! There are a couple reasons:1. DC motors typically use brushes, which are both noisy, and can wear out2. AC RC motors come is a wide range of Kv ratings, so I was easily able to find one that matched the RPM of the trainer drive shaft to get us to the ideal 10-15 charging volts.

Thanks so much, Matt! Really appreciate the positive feedback.

I've got to try these - peanut butter cups are my kryptonite! Thanks for sharing, well done!

How about a Human Power contest?

Very good point, Lorddrake! One of the very reasons I like this Drok meter as you can set it up to blink the screen when you reach an upper limit on voltage. I used this meter for the box you see in the video mounted on the bike. Another nice feature of this meter is it 'remembers' the total watt hours generated even if you stop pedaling.

Good tip! Thanks Lorddrake.

Yes, you certainly could, depending on your fitness level. That balance charger should work perfectly, with the added benefit that it accepts a pretty wide range of input voltage. The great thing with these balance chargers is you can always adjust the amperage down if you physically can’t maintain the max wattage needed to charge a battery.

I see your quandary - let me try to clarify. To your last statement - the current (amps) will be defined by the load, so when I’m charging my 5500mAh 11.1v Lipo battery, the proper settings to charge it are 5.5 Amps and the volts are managed by the balance charger, starting out at whatever the battery is at, usually around 11.2v. Watts = volts * amps, so we get 61.6 watts of resistance while pedaling. Not exactly - the charger isn’t 100% efficient, so that load is more like 70 watts. The wattage will actually increase as the battery charges until the battery gets to 12.6v, at which time it will taper off as each cell reaches a fully charged state (which makes for a good cool down). To your question about which motor to choose, what you really need to determine is what R...

I see your quandary - let me try to clarify. To your last statement - the current (amps) will be defined by the load, so when I’m charging my 5500mAh 11.1v Lipo battery, the proper settings to charge it are 5.5 Amps and the volts are managed by the balance charger, starting out at whatever the battery is at, usually around 11.2v. Watts = volts * amps, so we get 61.6 watts of resistance while pedaling. Not exactly - the charger isn’t 100% efficient, so that load is more like 70 watts. The wattage will actually increase as the battery charges until the battery gets to 12.6v, at which time it will taper off as each cell reaches a fully charged state (which makes for a good cool down). To your question about which motor to choose, what you really need to determine is what RPM range you will be in, from low to high. If you’re using a bike with multiple gears, you can always adjust the RPM by shifting up or down. The load will remain relatively constant, and as long as you are in the voltage range of the charger (10v-28v), the charger will be happy. I think your calculations to go with a 63kv motor are off a bit as this would put your voltage at about 68 volts @ 15MPH (using a mountain bike tire as I have in my calculations). Don’t overthink the motor, I’d go with a 320kv for a mountain bike tire and a 350kv for a road bike tire.

Thank you! Glad you like it. No reason why you couldn't use this to charge an RC LiPo battery, although I haven't tried it. The input voltage for a typical B6 IMax or similar Lipo battery charger is 11-18v, right in the sweet spot of this design. The nice thing with using a Lipo battery is you can put a lot of watts (50, max) into the battery in a short time. Typical USB battery packs will only accept 5 watts charging, and quick charge 3.0 battery packs top out at 18 watts. I like your idea! I'll have to get a Lipo battery and one of these chargers ( http://amzn.to/2jzAoKf ) and try it out! As long as the volts out of the Lipo are between 9 and 24, then any good USB car charger will charge your devices with the battery. Great thought!