"I made a little graphical representation showing my 'common loop' independent setup that I have envisioned, next to the Viking semi-independent drivetrain and the DaVinci independent. I've highlighted a few things in color. Freewheels are in cyan/blue, fixed cogs are in purple, and 'weird' (left-hand) crank cogs are in red.
Kudos to Brad for designing the Viking drivetrain - After graphing it out, I realize it's quite tidy!"
Read more and join the discussion: Fully independent drive system
The Viking is a very unique tandem trike that includes an independent transmission system that allows one rider to stop pedaling without affecting the other. The Viking Tandem Trike uses commonly available 20mm disc brake hubs, so there are no hard-to-find or overly expensive components needed. The frame is completely made of square steel tubing, and everything else on the Viking Trike can be found at bicycle shops or hacked from scrap bicycles.
The building process is designed to allow anyone with a Do-It-Yourself desire to finish his or her own version of the Viking Trike without requiring previous bike building experience or specialized tools and skills. The plan is laid out in a format that makes customization or alternate parts usage a breeze, so you will certainly be able to include your own imagination in the process of building a recumbent trike.
If you have been eying up those expensive imported tandem trikes, but think $8,000 is a bit too steep of a price tag, then get out your tools and build it yourself! For thousands of dollars less than the price of a basic tadpole trike, you can create your very own tandem trike that will rival many of the factory built machines available.