CeramicSpeed DrivEn - Faster than any chain

Discuss light weight issues concerning road bikes & parts.
kgibbo1868
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by kgibbo1868

Pain is my friend!

by Weenie


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TonyM
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by TonyM

I pretty much like that they try to find an innovative drivetrain!
Not sure however if this is what we need.

kgibbo1868
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Joined: Thu Jun 21, 2012 6:36 pm

by kgibbo1868

TonyM wrote:
Mon Jul 09, 2018 4:18 am
I pretty much like that they try to find an innovative drivetrain!
Not sure however if this is what we need.
I think it is pipe dream material, but I like the look and concept. :-) Still quite a few hurdels to overcome, like shifting. :-)
Pain is my friend!

lostrainbow
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Joined: Mon Apr 02, 2018 10:54 pm

by lostrainbow

I am quite worried about the durability of the bearing and cassette. Other than that, it is really sweet!

2lo8
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by 2lo8

I guess that's one way to mitigate friction losses from bevel/grown gears.
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jasonbrim
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Joined: Sun Jul 08, 2018 7:30 pm

by jasonbrim

It's incredibly noisy though - spun the cranks on it at Eurobike yesterday and it makes a LOT of noise.

It's only a concept though...could be improved if they develop it further with a bike manufacturer. It also didn't free-wheel - was a fixed gear.

It makes you wonder what's wrong with a belt drive and internal hub.

TobinHatesYou
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by TobinHatesYou

Chain drives are already 98% efficient in the optimal chainline at 300W, so something like this is chasing 5-6W, and more realistically 2-3W.

The trade off is having a pizza pan sized meat grinder that will surely need a shroud to be practical/safe. It'll be a sail in crosswinds.

In addition there's so many points of failure. There are two pinion gears on the shaft and each has about a dozen tiny bearings comprising the "rolling teeth." The easiest way to implement shifting is to stick a battery inside the shaft, a motor and a radio. Otherwise they'll have to get creative with either dynamo tech, induction or low-friction conductive surfaces on one of the braces holding the shaft in place.

I think this is a total non-starter. The future for most cyclists is internal gearing of some sort or simply electric. (If you really wanted to make a fitness bike electric, you could use a super capacitor powering a motor and induction coils at the crank...no transmission necessary.)

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onemanpeloton
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Location: Edinburgh, UK

by onemanpeloton

been following the release of this.

I love it!

There isnt enough innovation in the industry, this is finally something to get excited about
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alcatraz
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by alcatraz

Just brainstorming here... :D

What about putting essentially a front wheel in the rear dropouts, with a special rim that has a groove on it's right side with teeth going all around.

Then by using a crank that has some internal gear mechanism to spin a "big chainring" backwards at a certain user variable gear ratio from the crank arms, the "chainring" connects to the teeth in the rim. Voila.

Shrike
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by Shrike

Love it, hope SRAM or Shimano fork out for the patent and go to work.

TobinHatesYou
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by TobinHatesYou

alcatraz wrote:
Mon Jul 09, 2018 11:43 am
Just brainstorming here... :D

What about putting essentially a front wheel in the rear dropouts, with a special rim that has a groove on it's right side with teeth going all around.

Then by using a crank that has some internal gear mechanism to spin a "big chainring" backwards at a certain user variable gear ratio from the crank arms, the "chainring" connects to the teeth in the rim. Voila.

1) Without a freehub, coasting through such a tall gear would have a lot of friction losses.
2) You don't want bigger gears on the rear wheel. The CeramicSpeed pizza plate is bad compromise because the gears on the shaft can only be so wide before they take up too much frontal area or otherwise impede on the design of the rear triangle.
3) Not very cost effective to make such an intricate wearing component so large and integrated in a rim.

Come on, you can think up something better. :)

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tymon_tm
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by tymon_tm

love the idea, for sure it's something to work on in the future. I still think the future holds for us something more neat regarding the rear, IMHO whatever it's gonna be powered by (and by the looks of it, not necessarily a chain) it will need to be more hidden and compact (like a nexus hub)
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TobinHatesYou
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by TobinHatesYou

2000W electric motor + supercap. Induction at the cranks. No transmissions necessary at all.

hambini
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Location: Bristol UK / Cologne, Germany

by hambini

They have been very careful with their marketing tripe.

They said i was less "sliding friction" than dura ace, the total frictional loss might be lower but there are significant mechanical losses. When the drive is rotated through 90 degrees twice, the loss is a lot because forces are generated in non ideal directions.

This will never take off because the drivetrain will need very accurate alignment, frame suppliers can't get bottom brackets right so they are totally screwed with this.

Hambini

by Weenie


alcatraz
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Joined: Mon Aug 29, 2016 11:19 am

by alcatraz

I'm thinking a dual belt drive. One on each side of the crank. (and a rear hub with narrow spaced internal gears)

Similar to a dual chainring setup one side drives at a time. The user can choose which side to engage. One side is small/big, the other big/small.:D

Or maybe a chainstay integrated driveshaft?

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