Do you ride a hybrid, a commuter or other bike and thought I want to get rid of my front derailleur? Possibly not, but a grouping of fellows from Poland have got together to come up with a front gear system with a difference.
It is called the Efneo and is a 3-speed front bicycle gearbox to replace your derailleur system. This means it has one chainring which has an internal gearing system that will rotate the chainring at three different speeds. It is an equivalent to a 28/40/50T front crankset. Presently they are running a crowd sourcing campaign to raise the funds to get this product to market.
This means you get ratios that are pretty much the same as you would expect from a standard 3 chainring derailluer system. That makes it comfortable – the gaps between gears are not too big, not too small.
But it has one major difference to any other planetary gearboxes available on the market, has one specific feature:
you can upshift with full load (e.g. you can push the pedals with all your strength and change the gear to the higher one).
when you want to downshift, you need to stop pushing for a fraction of a second to let the gear change. It’s very easy to get accustomed to it and after a while you will do it without thinking about it.
Check out their funding campaign and videos:
How does it work?
The technical information is available here.