22 gears with no front derailer

Also claimed to save 17watts over other gravel bikes via it’s aero design.

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Also discussed on GCN recently:

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I really don’t see the point with di2 having automatic front shifting. But the 17 watts of aero saving is interesting

That looks like a lighter internal gearing system than the Shimano patents.

Interesting to see where they go with this tech. Could be appealing from a maintenance and robustness standpoint.

From the 2nd link in the OP:
“The brand also believes its system is more efficient overall than a conventional 1× setup because it reduces the amount of cross-chaining.”

Er - why? You won’t use the entire cassette? Also - a planetary gear reduction system (I assume one gear is fixed, the second one is a reducer) does have losses, and not small one, so whatever gains would come from “less cross-chaining” would largely be offset by the losses when using the reducer.

Confirmed from Classified’s web site - one gear is direct-drive, no loss, the other a 0.7 reducer.

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It’s 2-speed only.

I should have looked deeper. I’m at work and only browsing, sorry.

I think they picked the wrong ratio, as they could have improved on the usable range compared to a front derailleur by having more of a reduction. I think a 0.5 (or even lower) reduction would have been more interesting, you could get a really wide range, with also fairly close gear spacing.
I think the only real downside to a larger difference would be shifting the ‘front’ would be more disruptive, and would require more rear shifts. This could be largely handled by an all electronic drive train.

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Because front derailurs are miserable.

They’re not that bad on a road bike. Pain in the a$$ on a mountain bike.

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Yeah I’ve never thought they were bad on a roadie.

It is not meant to be a hub gear, but replace a front derailleur with two chain rings. And at least gearing-wise, it seems to do exactly that.

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They are bad also on a road bike. In two races last year my chain seized at 60+ km/h. Fortunately, I was able to get it unstuck after a few seconds, but kinda disconcerting when you have to deal with a technical problem on a technical descent in the rain. :slightly_frowning_face:

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I can see a clear future in this. The only problem are the big boys (shimano, sram, campa,…). If it is a game changer they will either buy them or develop something similar if they haven’t already.

Anyway looking forward to test this…

Geets

Just to be clear - apart from the wireless shifting part, there’s nothing earth-shattering about an in-hub planetary gear mechanism. The Sturmey-Archer 3-speed hubs from the 60’ used the same mechanical concept. Rohloff has pushed the concept to 14-speed, while still using cable-driven shifting.

Shimano has internal gearing hubs since years. The Alfine and Nexus lines have 8-speed hubs, including disc brake (and even coaster brake) versions.

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image
SRAM 3-speed hub with cassette. They dropped that product.

Thx for the info! I should have known this, my children’s bikes have those inner gearings.

There’s a fascinating article by John Allen on Sheldon Brown’s web site on the topic. Well worth reading for the mechanically-enclined.

https://www.sheldonbrown.com/internal-gear-theory.html

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You can’t really go further than 2:1 on a single-stage planetary gear reduction. The efficiency and manufacturability drop as you increase the ratio.

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I think it can be a huge improvement in MTB and cyclocross… The front mech always catches a lot of dirt/mud. Also the shifting under heavy load can be an advantage.