ELIMINATOR INNER TUBE
The Eliminator inner tube was sold in the early 1980’s. I cannot find a current online source for them, and I do not know whether they are still available.
I bought a set for front and rear and used them for a few years. I found the ride harsh, and it seemed that more pedaling effort was required than with my former pneumatics.
The main reason I got them was that I was doing some validation rides involving bike transport by air, and the idea of getting a flat tire scared me, as it could shoot down the entire trip.
The Eliminator inner tube was simply a piece of firm plastic hose, cut to the proper length and inserted into the bike tire in place of the former pneumatic tube. It was sold in various cross-sectional diameters to accommodate a range of bike tires.
My conclusion, after using the things for a few years, was that they were not a good measuring tool.
Those curious for more information can read all about it in Measurement News issues 5, 11, 16 and 30, which can be accessed through www.rrtc.net.