View Full Version : Screw Transmissions.

11 November 2010, 0403

OK. Screw transmissions. However. This is an example of how completely awesome this forum is. On the transmission thread, Rob mentioned 50cc 9-speed roadracers from the '60s. This is something I've been trying to track down for decades. Decades, I tell you.

http://sphotos.ak.fbcdn.net/hphotos-ak-snc4/hs931.snc4/74475_1735243460414_1218396040_31976262_7774279_n. jpg

My first bike was a Honda CL100 I bought from Sportsman Cycle in West Boylston, MA. They had one of these on the floor. I always thought it was a 90, for some reason, but this is it.

Clearly, it was a vision that has damaged me for life.

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I see two hub motors. And just when I'd decided hub motors were a lost cause.

11 November 2010, 0753
Make a decision Man...... :):)

The technology is changing so fast we may never get anything built! :confused:

11 November 2010, 0803
Screw transmissions.

I believe the more technically correct term would be a worm drive tramsmission. That could be an interesting way to set up shaft drive with a very high gear reduction.

11 November 2010, 0920
The 1950's English Sunbeam in-line 1000cc motorcycle used a worm-drive to turn its shaft-driven rear wheel. It didn't work too well. The bike looked great, but the screw wore out rapidly and used a lot of power, which inserted a lot of unneeded heat into the wheel hub. My recommendation is to keep your worms in the ground and let the robins pull them out when they need them.