In the mid-eighties a number of innovations appeared to address the new and expanding mountain bike market. The majority didn’t survive more than a season, as the real world intruded on the performance measured in a pristine laboratory with no mud or bike crashes.
The Browning Automatic Transmission came from the same industrial family as the Browning Automatic Rifle. The battery operated shifting opened a hinge on the chainring to shift the gears. It turned out that mud and wet wiring often interrupted the function. The Browning transmission sank without a trace.
This article from the geek mag Bike Tech was written by one of the designers, and reflects the optimism he had with the product when it was introduced.
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