Originally Posted by
voor9
There's a LandRider auto shift, it needs though a plastic v-belt disc to control a v-belt behind the freewheel. Interesting derailleur though, no other wires needed for shifting. Shifts when pedaling harder, troubles might come when on smallest cog and you have to maintain certain speed:
LandRider Auto Shift derailleur
And Bikemanforu has done at least two videos about this thing to the Youtube...
That's an interesting design. The one I remember (as best I can remember) came with a bracket that mounted on the drive side of the rear wheel, and likely operated on a similar principle. But, as I said, that was around 25 years ago, I've slept since then, and I didn't look at it closely enough to figure out how it worked when I did see it.
I still say there's nothing wrong with manual shifting that requires an automatic shifter. I can imagine if it were a $19.95 "as seen on TV" product the commercials would have all us cyclists in black & white struggling like crazy to shift gears on our bikes.
I don't understand why that page called centrifugal force "mythical," though, since it is very much real.