Tandem Progress:

I have had many interruptions over the summer that stalled the work on the new tandem. Problems developed in two areas. First the hydraulic brake line for the rear wheel was too short. The tubing is very exclusive and very expensive. Also the replacement pieces seemed to come only in the same length as the one I had. I enlisted the aid of long time friend and bicycle “wrench” extraordinaire, Ray Scholl, and he directed me to Universal Cycles in Portland. I found just what I needed there.

Purple and Newcomer
Purple with the New Tandem

I spent about the whole day yesterday adapting a three meter segment of brake line to fit the new bike. I managed to get mineral oil all over myself and the shop trailer trying to bleed the brakes, but everything works as planned.
The other thorny problem was an idler to take up slack in the drive chain. Normally that is the function of the rear derailleur, so I built a mount and installed a derailleur, simple! The first ride proved otherwise. The derailleur sticks out over two inches and clips my ankle bone with every pedal revolution.
Once again Universal Cycles came to the rescue. They have a rather extensive collection of chain tensioners that are used to convert multi-speed bicycles to single speed bikes. They also have a very convenient return policy. I was able to purchase a couple tensioners that they had in stock and take them home. I very carefully opened the packages and gingerly tried each one in place of the derailleur. One was still too fat, the other showed some promise but didn’t take up quite enough slack to meet my needs. I then went on-line and ordered a similar tensioner but with more chain take-up and had it set up for in-store pickup. I restored the packing, and Judy and I jumped on Max and buzzed down to the store. I compared the “almost good enough tensioner” with the new one and all looked promising.
Bending Chain Drive
Closeup of Bending Chain Drive

The new tensioner is perfect. It clears my ankle bone and takes up enough chain to have two ranges of gears. The bicycle will have a double chain-ring crank and a Nuvinci hub with 360% speed range. Each rider gets their own gear shifter and the seats will be adjustable so either of us will be able to captain the bicycle.
Judy and I climbed aboard the new bicycle Saturday and rode around the parking lot here at the Elks Lodge where we are staying in Hillsboro, Oregon. I am really stoked! The new bicycle has both front and rear wheel drive. The front wheel drive uses a “bending chain” concept. That is, as you ride and steer the chain bends to follow the wheel. The new bicycle has very light steering and has a nice balance to it. I was steering it with one finger. I would have tried riding with no hands except there was some uproar developing in the back seat.
Click here to see video.
Path is also all wheel drive, but it uses a swinging front end. That is your legs bend with the steering. The steering is heavy and there is a lot of inertia to overcome to swing both your legs and the sub frame and wheel. However, over the ten years that we rode Path, we racked up 13,526 miles.
Just a side note: Four days ago, on Thursday, our granddaughter, Georgia, soloed on her bicycle with no training wheels. Her next challenge will be to learn to ride her new birthday bicycle with larger 20 inch tires. I hope to have a copy of the video in my blog within a day or two, but meanwhile you can see the video posted on our daughter’s Facebook page at http://www.facebook.com/reneetice.
Meanwhile there will be some photos of the new bike and the bending chain drive on my website at https://www.dinsmore-enterprises.com/?p=2441