Quoted By:
WINNER - Christian Seeley: "This is the Browning Automatic Bicycle Transmission. It has been around, in one form or another, since the late '70's. The chainrings are split and hinged (that is the silver portion). The split/hinged portion are pushed into the next lower chainring when shifting and the chain just rolls off onto the next chainring as the rider pedals. As I said, the product has been around for a while, but it never has caught on, except for maybe some comfort/hybrid type applications. Probably not durable enough for hard mountain biking or road riding. My first exposure to it was in the '80s when I was a BMX rat, my hero Harry Leary was testing a 2 speed Browning transmission for BMX racing. He went back to using a regular 1 ring set-up the next season, if that tells you anything."
RUNNER UP - Greg Balco: "Awesome. That thing is either a Browning Automatic Transmission or Suntour's later attempt to make a production version of the Browning. The hinged sector of the crank flops back and forth to pick up or deliver the chain directly to or from a different ring -- the flopping is driven by an electromagnetic actuator with a battery and a handlebar switch. I walked into a bike shop in Golden, Colorado on a Sunday morning in 1993 and the shop owner had a prototype bike that had one of these on the front and, even more amazingly, a similar one on the rear end that had four gears and replaced the rear cluster. Two sets of handlebar-mounted buttons and, if I'm remembering right, an automatic-shift mode that tried to maintain pedal RPM in some range. This design is one of the most impressive machining accomplishments ever put on a bike...it's too bad Suntour never managed to deliver a production model."
