From "CYCLIST" Magazine June 1985, pages 52-53. I lost the original article. All I have is a photocopy and the pictures aren't good enough to scan in. This is the text of the article, my pictures show the construction. CYCLIST magazine is long since defunct.
Those readers who recall the Gearing Institute's definitive treatise on ultra-wide-rage gearing for bicycles (CYCLIST, December, 1984) will be gratified to know that the Institute is still at work maximizing the efficiency and elegance of bicycle gearing systems. Following is a report - exclusive to CYCLIST - on the Institute's latest project.
To the growing ranks of superfluous unconventionality in bicycle gearing, as exemplified by the Houdaille Power Cam and the Alenax Lever-Drive system, we of the Gearing Institute are delighted to contribute our Torque Stomper "Tri Via" two-speed gear system, the first non-conventional gear system designed specifically for people who don't know anything about riding bicycles. Not only is the "Tri Via" system foolproof in operation - no unpleasant shifting is necessary - but the subjective sensation of increased power and speed over conventional systems is so pronounced that no amount of rational argument or objective proof will dissuade the true believer.
Like most other non-conventional drives, the "Tri Via" system is actually an up-graded, high-tech, modern version of an idea that was already tried in cycling's early days. In this case, the design was brought to our attention by a fieldworker (Mr. Pedlin) who discovered it in the trash behind a bike shop on Ludlow Illinois, whose owner was clearing some space in back for a Coke machine.
The information made available to us included a number of diagrams and technical drawings, a U.S. patent application and several, er, love letters in which prominent reference is made to the prosperous future that awaits one cycling swain and his intended bride when their fortune is secured by the universal acceptance of his "Design For a Method of Providing Multiple Gears to the Safety Bicycle."
The inventor of the "Tri Via" system seems to have be one Egberto Murphy-Schultz, a turn-of-the-century British immigrant to our great land who eventually married someone else and made not a fortune but a living, at least, from improvements to the plastic veterinary syringe.
But we digress; all that came much later, as in his early years Murphy-Schultz was totally absorbed in his efforts to introduce to the cycling world a bicycle that could be pedaled three different ways, in two speeds, without shifting.
As it happened, the least of his problems was strictly technical. The "Tri Via" system is ingenious, but not overly complex or mechanically exacting, and Murphy-Schultz had achieved an operational prototype within a few months of starting work. With the help of the local blacksmith and an implement repair facility in nearby Paxton our young inventor was soon "scorching" through the countryside thereabouts, causing many an ordinarily imperturbable German farmer to look twice at him rolling down the rural lanes pedaling backwards, tipping his had and waving, "Cheerio, wot?"
His first inkling of the dimmer days ahead came on the occasion that he demonstrated the system to his betrothed, the lovely Hilda Osterwald.
"But I'm pedaling backwards, don't you see," he called to her.
"So what?" she hollered back. "Maybe if you could ride that bicycle and feed these hogs at the same time, I might be impressed."
Egberto didn't hear her. "Now I'm pedaling forward again, see?"
Hilda flung another handful of corncobs from here bucket. "There, there, little piggie ... That'll put a curl in your tail."
Consider, then, the plight of poor Egberto - he'd come up with a surpassingly silly idea in an age that lacked both the mass communication media and the genius for over-promoting the trivial that were necessary to insure its immediate acceptance by an uncritical cycling public. All he could say, in essence, was, "Here's a bike you can pedal backwards or forwards." Cyclists of the time rightly inquired "What's it good for? Why is it better than what we already have?" Egberto Murphy-Schultz had no ready answers and his idea died aborning.
No such obstacles exist, however, in the modern, high-tech age. We at the Gearing Institute showed the "Tri Via" system to a number of highly qualified engineers (each of whom had at least six pens in his shirt pocket) and all of them could see instantly how greatly superior to every other design the system is. A selected group of non-cyclists was asked to give the "Tri Via" gear an unprejudiced, unbiased trial and all reported that it rode "just like a bicycle" and that if it had a wider seat and higher handlebars, it would be "even better than a regular bicycle," though still not as good as watching TV.
Further, several experienced cyclists who ride a-lot have indicated that, pending some incidental consideration such as an expert's consultation fee, they would be willing to test ride the system and confirm finally that it is, in fact, the best gear system ever invented that enables the rider to pedal both backwards and forwards.
The foregoing examples seem a certain indication that the narrow-minded, short-sighted technological philistinism that prevailed during Egberto's day is clearly a thing of the past. The question for the 80's and beyond clearly will not be, "What are we supposed to do with it?" but, "How did we ever live without it?"
The mechanism is simple both in operation and in construction; a brief description follows. First, a 16-tooth Suntour BMX freewheel is threaded halfway onto a standard five-speed rear wheel. Next, an English bottom bracket adjusting cup is threaded into the freewheel, then a second 17-tooth or 18-tooth freewheel is threaded onto the remaining threads of the adjusting cup.
The drive chain is then drawn around the chainwheel and arranged as show in the accompanying photos. The chain passes from the stay-mounted idler over the outside freewheel forward to the top of the chainwheel and around, and then from the bottom of the chainwheel top of the inside freewheel, over, and back to the idler. Little more need be said, as the logic of the system is immediately evident when it is observed in operation. Generally speaking, slightly worn or loose chains, such as the Shimano Uniglide, run quieter and more smoothly than new ones.
As presented here, the system provides a conventional, forward-pedaling low gear and a high gear in the backwards-pedaling mode. The system can be set up in the other configurations, and we herewith commend it to further experimentation on the part of those so inclined.
The "Tri Via" system is not covered by any patent protection, being, as it is, constructed from proprietary components and in the public domain at any event. At first we thought we'd make a bundle off it, but as usual, we had to opt for the old unselfish-non-profit-contribution-to-the-larger-fund-of-cycling-lore gambit. Doggone shame, that; we really thought we had a hot one here, bucks-wise.
The sensation of traveling forward while pedaling backwards is its own reward initially, and has been likened by some riders to the "moonwalk" routine in contemporary dancing (the use of one sequined riding glove is optional). Riders with one leg stronger than the other can "rock" the cranks at mid-stroke, pushing hard on the high-gear cog with their strong leg and pushing easy on the low-gear cog with their other leg. Back and forth, back and forth; it's easy, and it's fun because it's a natural motion.
In closing, we would caution enthusiasts about a potential problem arising from the use of the "Tri Via" on shop-errand bikes, an application that will no doubt account for the majority of systems in service. Do be careful when using a "Tri Via" bike for the Saturday morning donut shop run, as the sight of it in operation may cause serious mental disorientation in hung-over patrons who are sucking down coffee at the counter as you ride by. Be considerate.
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