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Comment by tasty_freeze | Hacker News Reader

So this new system saves about 2% of effort, which is large savings for competitive cyclists.

For 99% of cyclists, though, it doesn't matter. The overwhelming part of your work goes into air resistance, then rolling resistance at lower speeds, and probably the chain in last place.

In the last few seconds of video the mechanism can be heard -- oh boy, it is loud. The pawl in bikes can range from nearly silent to annoying, but this one seems to be even worse.

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They claim 99.2% efficiency (in lab conditions) and compare that to 97% for a chain drive. In lab testing, bicycle chain drives have been found to be 98.6% efficient: https://web.archive.org/web/20080306054536/http://www.jhu.ed... so that would be an improvement of 0.6% rather then the 2% quoted..

And also most people's bikes aren't perfectly maintained.

Probably this system also loses efficiency if not perfectly maintained.

Looks like it has less exposed moving parts that a classic bike. Could be easier to maintain / clean / lube.

Not the naked variant — it's about the same as a chain derailleur. Maybe with the cover. It doesn't exactly look easier to clean that giant sharp dinner plate. Idk.

But perhaps for the average cyclist this "split pinion works under load shifting mechanism" is easier to use and more reliable.

To me it sound like it is possible to shift only one gear at a time and only when pedaling. So if you stop at traffic light with high gear, you can not switch to lower gear while waiting for the light to switch.

Most chain drives can't switch gears without pedaling either.

Internal gear hubs typically (always?) can change gears when not pedaling, derailleur gears can't.

And most chain drives are derailleur systems, not IGH, so you're both right :-).

And most IGH systems are chain drive as well, so all three of you are correct :-)

if chain includes belt.

My experience with Shimano gears is that if I change when stopped or while not pedaling the change completes when I start pedaling again. The only important thing is to go easy on pedals if starting from still and don't change both the front and the rear gears.

As a category of bikes that also can’t do this is quite popular this isn’t a deal breaking issue.

You definitely can, just hold the front brake and push the handlebars forward to lift off the rear wheel. It's even easier if you're using clipless pedals.

> For 99% of cyclists, though, it doesn't matter.

What matters is clean look. Chains are dirty and look dangerous. Good bikes (like Dutch omafiets) cover the chain, but if scaled manufacturing cost of this system is $30 extra, people would pick this one.

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