DIY Bicycle-Powered Cell Phone Charger from Makezine, Google+ & RadioShack


Earlier in the week they showed you how to make a bike exhaust tailpipe to amplify the card in the spokes.

The second bicycle themed summer Maker Camp session from Makezine and Google+ goes live Saturday, July 13, at 11am PT/2pm ET on Makezine’s G+ page. They’ll offer live Q&A for the project there, or you can grab the project details from their website and do it on your own time. No, it ain’t pretty, and perhaps not even all that efficient, but it’s as much about learning as it is actually making the thing. Which might help you figure out ways to hack existing dynamos (like this and this) to suit your own needs.

Check the video below to see how it works…


jake - 07/12/13 - 10:11pm

If your this guilty about the purchase of your cellphone and also hate going fast on a bike just move to India and go on a pilgrimage: the rest of us a’int ever using this kinda thing

JimmyZ - 07/12/13 - 10:56pm

would it be powerful enough to energize a personal massager while I ride? that would be very therapuetic!

Ed R - 07/13/13 - 1:23am

I love the way it’s so integrated into the bike!

MikeK - 07/13/13 - 4:30am

If you serious about charging your GPS or cell while riding better invest in something that will really work in the end 😉

There are various other cool options like E-Werk, pedalpower etc. My favorite is the tout terrain PLUG that replaces the headcap. Nice integration but price tag maybe a little high compared to the DIY kit here……

Rico - 07/13/13 - 2:14pm

That particular style of generator is a terrible energy sink – from your legs. You have to keep pedaling, even downhill to keep your speed up.

No doubt, the inefficiency comes from being mounted perpendicular to the wheel rotation. Seems to me that a more efficient generator could be built with a drive wheel that drops directly onto the tire (like a Solex motor) and a small belt drive or nylon gear to turn a generator that turns on an axis parallel to the wheel axle. Moreover, the power need of an electronic gadget is pretty small compared to the standard flashlight bulb at the heart of the bike lamp.

I would build one myself but I really don’t have the time to squander on a Kickstarter campaign and all the social media updates.

T - 07/14/13 - 10:15am

This is the least elegant hack I have ever seen.

drider - 07/14/13 - 3:52pm

I’d rather run out of charge. This is one UGLY, hacky and ghetto solution. Wow.

Andre - 07/15/13 - 12:48am

Rico, what you speak of is called a Bottom Bracket Dynamo or Roller Dynamo. They’re not common in the USA.

Rico - 07/15/13 - 1:09am

Yes, I found a couple by that name with a rubber or abrasive wheel that rides the tire. Here is another one that uses teeth in the chain. Pretty slick device but it definitely lacks the charm of the Frankenbike original above.

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