Electric Bikes - Help with eBike idea

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Mr_Wrench
12-15-09, 09:27 PM
Hi everyone,

I'm a long-time bikeForum member new to the idea of electric bikes. I was hoping to get some thoughts on the feasibility of converting my Azuki Single Speed bike into an electic. I was thinking I'd go with a hub motor on the rear. I have a really solidily built steel rim, all steel tubing. I also have a steel double-butted fork which might make it a better candidate for a front-wheel hub? This is where you guys come in. Which eletric motor/battery would best this bike? Also, it should be noted it has 27'' wheels.

Any thoughts and suggestions would be appreciated. I'm looking to do this on the cheap, I don't have more than a couple hundred to put into it. I'm very serious though about making something strong and built to last. I just don't have the dough

My whole design idea is basically efficiency to the max. Right now, as you can see in the picture below, I have a pretty big 3:1 gear ratio going on. I figured with the right motor I could do some serious milage with pedal-assistance, while pedaling at my usual cadence of 70-80 RPM

http://www.flickr.com/photos/abracadabra-/3834635222/in/set-72157607745426742

Thanks in advance!

nwmtnbkr
12-15-09, 09:44 PM
Hi everyone,

I'm a long-time bikeForum member new to the idea of electric bikes. I was hoping to get some thoughts on the feasibility of converting my Azuki Single Speed bike into an electic. I was thinking I'd go with a hub motor on the rear. I have a really solidily built steel rim, all steel tubing. I also have a steel double-butted fork which might make it a better candidate for a front-wheel hub?

Any thoughts and suggestions would be appreciated. I'm looking to do this on the cheap, I don't have more than a couple hundred to put into it. I'm very serious though about making something strong and built to last. I just don't have the dough

My whole design idea is basically efficiency to the max. Right now, as you can see in the picture below, I have a pretty big 3:1 gear ratio going on. I figured with the right motor I could do some serious milage with pedal-assistance, while pedaling at my usual cadence of 70-80 RPM
x
http://www.flickr.com/photos/abracadabra-/3834635222/in/set-72157607745426742

Thanks in advance!

Welcome. That's a beautiful bike and a good choice for an e-bike conversion since it's steel. If you're willing to consider a non-hub motor, you may have more options for a low-cost conversion. Here's an link to an interesting discussion on Endless-Sphere's general e-bike forum on inexpensive e-bike builds. http://endless-sphere.com/forums/viewtopic.php?f=3&t=13789
It will be difficult to get a hub motor, controller, throttle and battery for under $200; there seems to be a premium charged for building a hub motor wheel. Also, be prepared for battery sticker shock if you're thinking of using newer, more efficient battery technology, like LIFEPO4.

I just converted my 21-speed mountain bike this summer using the Currie conversion kit, which is a 450W, 24V non-hub motor kit. My total cost was $279 (with free shipping from the superkids.com--they still have it at that price) and the kit had 1 24V, SLA battery pack. There's an added advantage for me with this kit; it's got great torque, which I need for the hills here in the Rocky mountains.

If you want a hub motor, a rear wheel installation is safer. You'll definitely need toque arms for either a front or rear hub motor installation. I'd encourage you to read threads at Endless-Sphere--there are many DIYers on that forum. You can get some good ideas.

Good luck.