18 gears in the bb

[benb]

That looks very interesting.
How does it work?

 

[ComedyPilot]

I've also looked at this and thought, 'How will that affect the final drive?'

Especially with such a small chainring????

 

[MacB]

I'd guess that the chainring needs to be small as that, combined with the cog will provide bottom gear(direct drive?), then the other 17 scale upwards from there.

Not sure on the operation, all I can envisage is a hub gear moved forward, I'm sure there'll be exploded diagrams etc.

 

[ComedyPilot]

I just don't understand how putting gears at the 'input' of the drive before the chainwheel will affect the final drive at the rear wheel?

Someone will explain it soon, and there will be a lightbulb go on in my head, but until then I'm off youchoobing and wikipedia'ing for it.

 

[bikepete]

Someone gave a link to the patent PDF on page one of the thread - open that up, scroll past many pages and you'll find the gear tooth counts, internal drawings etc