Are Chainless Shaft Drive Bicycles a GENIUS or TERRIBLE Idea?

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🔧 Current Shaft Drive Bike Manufacturers:

0:00 - Intro
0:47 - What is a shaft drive bicycle?
1:33 - Reason #1
2:36 - Reason #2
4:23 - Reason #3
5:20 - Reason #4
6:15 - Reason #5
6:42 - The Driven Drivetrain
8:29 - Summary

[Cyclingabout]

QUESTION: Do you think the Driven drivetrain will make the leap from cool concept to derailleur killer? 🤔🤔

[Krieghandt]

when building solar race cars, our numbers were 93% for chain and 86% for shaft. that was 800 lbs at 1100 watts. which really adds up on a 300 mile race.

[MD]

considering bicycle manufacturers couldn't manage to get the tolerances right on pressfit BBs, it's highly unlikely they will get them right for a shaft drive system

[Default]

Shaft drive bicycles have found a bit of a niche in industrial environments (e.g. navigating around large manufacturing plants or oil refineries) where efficiency isn't a major concern and the reduced risk of falls from getting pant cuffs stuck in the gears is a decent selling point.

[kentslocum]

At this point, I need tires that stay inflated before I can even begin to worry about the efficiency of my drive train.

[asharkis]

When I was about six years old, my father attended a trade show and was fascinated by a shaft-driven tricycle (I believe it was called a Gear-o-cycle.) He bought one for me. It was bigger and heavier than the typical kid’s tricycle but not as big as an adult tricycle. It had a differential at the rear, but the welds that attached that differential case to the rear frame kept breaking. Eventually we gave up on it, the company that made it went out of business, and no other company ever took up a similar design.

[joshnabours]

2:53 - in motorcycles, chain drives typically waste 1 to 3 percent of the input energy, where shaft drives typically waste 5 to 15 percent of the input power. Bicycle shaft drives should have similar efficiencies to this.

[brandywell]

Some 15 years ago I went to a major bike show in the UK and was excited to ride and buy a shaft bike for leisure. When it came to my turn the bikes shaft gearbox had detached from the wheel because of loose fasteners and the show staff had not the ability to fix it.

[DCassidy]

I like chain-driven systems, but for mountain biking, the derailleur is so vulnerable to impacts. I think there's room for improvement.

[brandonguz]

I use a shaft drive bike for my commuter, and I also have a road bike with a traditional Shimano rear derailleur. Here in the Netherlands, having a shaft drive for cycling in the rain is a massive benefit. I have done virtually no maintenance on the bike in almost 5 years and I think the loss of efficiency is negligible when commuting at less than 100 watts (compared to other commuter/hybrid bikes I’ve owned in the past). I’ve also lived in dry, hilly cities and in that case, I agree that the a traditional bike would be much better.

[petersmythe]

me, an intellectual: Why do chains when you can do *GIANT GEARS*

[GamingNachos]

The shaft drive is like the rotary engine of the bicycle world

[TheWtfnonamez]

This problem reminds me of the bushcraft hatchet.
Everyone is always trying to come up with a high-tech replacement to the traditional hatchet. The old fashioned design has its drawbacks, mainly that its quite heavy, but in all other regards it excels. It is cheap, incredibly robust, cheap and easy to repair, lasts almost indefinitely, and mother natures plain wooden handle is both durable and acts as a natural shock absorber, protecting the users wrist from fatigue.
Over the years I have seen a myriad of alternative designs, all trying to make it lighter, foldable, multifunctional, or more compact. All these attempts end up causing massive negative effects, such as making it vastly weaker, causing terrible vibration in the handle, poor cutting, low durability, and almost ALL of these high tech solutions are more expensive.... and are worse.
The OG wooden handled, steel head hatchet nailed the design over a millennia ago. It is just the best design hands down, and you can get a basic one from Amazon for fifteen bucks, sharpen it, put boiled linseed on the handle, and you are all set for three generations of wood cutting. Just like the traditional bicycle chain, sometimes the problem has already been solved, and attempts to improve on the solution are not worth the effort.

[birdrocket]

Nitpick about 5:52, the shaft needs low tolerances. High tolerance means it is more accepting of error, low tolerance means it needs to be more precise.

[gregknipe]

perhaps the only bike related reviewers / offers facts and data. and no pimping products to fill a you tube presentation. as always, thank you for your hard work here.

[JD]

Coolest new thing Ive seen for bikes is an oval crank gear that made it easier when you were at the angle of least power and was wider where your leg was able to impart the most torque on the crank.

[bummer]

I actually owned a shaft drive bicycle about a year ago. It was old, there was a lot of slop in the system and it felt like I lost a bit more power between the pedals and the wheels than on a chain drive bike, but it was quirky and fun to use! Although I wouldn't recommend it. Also worth noting that it had three gears using a shimano geared hub.

[MyChevySonic]

As someone who has replaced driveshafts and chains on machines for a living, I'll take a chain over a shaft any day.

[StevenGoris]

The city rental bikes in Antwerp, Belgium have this drivetrain. They don't feel as smooth to drive as chain-driven bikes, you really feel the cogs when pedaling. I don't expect the tolerances to be very tight on these bikes but the fact that everything is super stiff and the cogs are so close to your pedals may have something to do with it.

[bololollek]

In mountainbiking: maybe a future for shaft drive!
Assuming shifting is possible and smooth it could be good for mountainbikes. It seems ressonable to think that it is more rugged than chaindrive, and if you crash or drop the bike, there is no derailleur to bend. It also will not flop around like rear derailleur.