Tribrid Project

Back in 2004 when I built my first motorized bike I played around with the idea of a tribrid for awhile using an electric hub motor and batteries along with the Chinese 2 stroke. (picture 1) I eventually abandoned the experiment and removed the electric parts from the bike because I felt that it didn’t add enough to make it worthwhile. At the time I thought that a generator might work to extend the range but all the ones I looked at were much too big and heavy.

Recently Michigan Mike (thanks Mike!) posted this video in a thread: Hybrid trike. This got me thinking about my tribrid project again. The generator used on the trike is much smaller than the ones I had looked at before. As a result I pulled out the electric hub motor and started work on it again. (picture 2, just a parts mockup at this point) I decided to document this project so I started a blog at Tribridbike.com. I have been writing about my other builds as well so that people can see where I am coming from and what I have done before. I invite you to check it out.

I am rather excited by the possibility of a series coupled tribrid bike. It would make so many thing possible. Unlimited range is one of the most obvious benefits but there are many many more. You could ride away from your home silently and engage the generator when you reach the thoroughfare making your neighbors happy. You can incorporate a sound system using your Ipod. Heck it has a generator. You can pack up your instrument and amp and go play music in the countryside. Or you can use it with your RV and have transportation and a generator with you when you are camping. Ride it to your jobsite and plug your power tools into it while you work!

If you have any other ideas how a bike like this could be used I would love to hear about them.

Cabin is right. Even with matched sprockets they torque curves for the two motors are completely different so they will only match up in one spot anyways. If you have regenerative braking on your I-Zip then it may be possible to charge the battery while running the 2 stroke. I'm not sure how efficiently this works however.

Some people have found benefit from this setup. One gentleman uses the electric to start the 2stroke. If run on electric or peddling the bike is basically silent so it can be used on bike paths etc.

The downside is the weight. Having the 2 systems on board makes it heavy. My bike will be heavy as well at first but I think I can get the weight down with some work.