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View Full Version : you know what, this is really really slick



Paul Pless
07-13-2018, 12:21 PM
and worth a repost

19297

birlinn
07-13-2018, 12:23 PM
You gotta da gear, Man!

Norman Bernstein
07-13-2018, 12:24 PM
I read about this yesterday.... it's partially 'smokeware', i.e., it doesn't actually work... they haven't figured out how to make it shift easily and smoothly.

I would also question whether two 90 degree rotational transforms are more efficient (less friction and loss) than a conventional chain.....

....but that's just me: the #1 cynic in the bilge :)

birlinn
07-13-2018, 12:29 PM
The bending forces on the driven disc in the lowest gear must be considerable- bet it jumps gears!

Canoeyawl
07-13-2018, 12:37 PM
It reminds me of a local patent holder, now deceased.
Toby, of Toby's Rasp Company made powed circular rasps for debriding tire carcasses for recapping, they looked very much like that...

willmarsh3
07-13-2018, 12:52 PM
But there's no chain to fall off.

peb
07-13-2018, 01:29 PM
What is the supposed advantage?

Paul Pless
07-13-2018, 01:35 PM
What is the supposed advantage?less friction

GregH
07-13-2018, 01:44 PM
The bending forces on the driven disc in the lowest gear must be considerable- bet it jumps gears!

I agree- that driven disk needs some backup opposite driving rollers.

oznabrag
07-13-2018, 02:00 PM
To facilitate shifting, the drive 'gear' needs each bearing to be spring loaded against the neighboring bearing.

A nice, stiff, spring with a travel limiter.

Each bearing only needs to move a tiny fraction of a millimeter to engage the disk properly during a shift in ratio.

You may well be able to do away with the spring, and just allow the bearings a little slop.

If each bearing can move to meet the next ring, and they all have the same 'slop' they will remain evenly spaced as they rotate under load, but will be able to deflect just enough to accommodate shifting.

sharpiefan
07-13-2018, 03:10 PM
I read about this yesterday.... it's partially 'smokeware', i.e., it doesn't actually work... they haven't figured out how to make it shift easily and smoothly.

I would also question whether two 90 degree rotational transforms are more efficient (less friction and loss) than a conventional chain.....

....but that's just me: the #1 cynic in the bilge :)

Don't knock skepticism -- it's what drives progress and (sometimes) keeps the SOBs semi-honest. :)

Sailor
07-13-2018, 03:25 PM
When will Rob comment this. It's right up his alley I think.

Jimmy W
07-13-2018, 04:04 PM
Have you seen this?

CeramicSpeed Driven - Fully explained


https://youtu.be/-9gQ1KRhesM

amish rob
07-13-2018, 05:08 PM
There is a reason that after all this time we still use chains on ďsafetyĒ bikes.

Quite simply, the bicycle drive train is as close to perfect as we can make anything work. Itís the best compromise between efficiency and strength going. So far...

Also, this drive for more gears boggles my mind. And huge cogwheels. I never had a gear larger than a 23 on a road bike (with a 42 front) or 28 on a mountain bike (and that with a 30 front, I never ran triples).

Then again, Iím a rouleur, and a flahute. Iím a masher. A grinder.

Also. Ceramic? Please. Just, no. No more ceramic on bikes, please. :)

Peace,
I Do Really Like Electronic Shifters, Though

Garret
07-13-2018, 05:43 PM
Lots of "it will" & "it could". IOW - doesn't seem ready for prime-time yet.

Cool concept though.

Gib Etheridge
07-13-2018, 07:15 PM
I can see where it might be a little lighter than chained bikes. That would allow for a backup pressure wheel on the other side of the plate, or, better yet, 2 counter rotating drive shafts sandwiching the plate. That would increase the friction enough to allow for the plate to be knurled on each face for traction and rubber drive rollers on the ends of the shafts.

Altogether I think there would be less likelihood of various mechanical failures and less adjusting and maintenance over all compared to using derailers.

Without having actually tried it I think I would prefer my version of the proposed system over the traditional chain and cassette system.

Too Little Time
07-13-2018, 07:37 PM
I think the idea is great. They seem to have explained a number of important details. The details they did not explain seem to have straightforward solutions.

If someone approached me wanting money, I would give it.

Gib Etheridge
07-13-2018, 07:50 PM
Shifting will be a problem. One mishap, like picking up debris, or the shifting battery being run down, and the whole assembly could self destruct due to misalignment. I think I'd rather rely on the chain and cassette and derailers.

What do engineers call the type of transmission I described? I didn't invent it, there is a name for it.

Paul Pless
07-13-2018, 08:00 PM
Shifting will be a problem. One mishap, like picking up debris, or the shifting battery being run down, and the whole assembly could self destruct due to misalignment. the one in the photo is a showcase piece
building it into an enclosed case would keep it clean and lubed and maintenance free and the case itself could help lend strength to the gear. . .

amish rob
07-13-2018, 08:03 PM
That thing is ridiculous.

We removed the cassette? No. You moved the cassette. And kept all the dish in the wheel. Dumb. The new one piece SRAM cassettes are mad light.

The ceramic bearings. Dumb. Just dumb.

Two points of engagement, eh? And those points are bearings? Yeah. Sounds robust. What’s that? Mud? No. No thanks. Check out Project 321 and the magnetic freehub body with, like, 9000 points of engagement. That’s robust.

Also, it doesn’t work. He says as much.

Last piece. What happens when you want to change gear sizes? Different front crank, say? What happens when just one of the ceramic bearings on the drive shaft starts to drag. Because that’s what ceramic bearings do on bikes. Wear out quickly.

It looks neato, sure. That is all.

Peace,
Robert

ETA: I have seen a bazillion of these type things at bike shows.

Paul Pless
07-13-2018, 08:19 PM
just guessing, but i bet the first derailleur circa 1860 was pretty ridiculous

amish rob
07-13-2018, 08:24 PM
just guessing, but i bet the first derailleur circa 1860 was pretty ridiculous
It was a logical solution, not the pursuit of an unrealistic ideal. Who cares if your design is ultra efficient if itís also finicky?

Or, not an improvement?

This design solves zero shifting problems. It only introduces a new, more complicated set of problems.

It is a beautiful thing, and a lovely experiment, but it ainít the future of bikes.

Peace,
Can Rebuild Campy Ergopower Shifters and Program Di2...

Duncan Gibbs
07-13-2018, 08:49 PM
That got me thinking (being a PTO driveshaft rolly polly sort of a guy) they seem to have taken the idea of a normal derailer and replaced it with a thingy. If'n you're going to go down this route I would have just miniaturised a normal shifting gearbox twixt the peddles and put a right angled gearbox on the driveshaft. All enclosed; all involute gears, auto-clutched like any normal gearbox. Works on little mowers, so why not on a bike.

This is a bit too much like, ahem, reinventing the wheel.

But it does look cool.

Old Dryfoot
07-13-2018, 09:17 PM
With the quality of current high end bikes isn't this idea firmly in the realm of diminishing returns? I mean a bike is what, 98% efficient? And just who is going to be able to capitalize on that added efficiency anyway? A handful of elite cyclist and not many others would be my guess.

But it is a wicked cool concept.

Jimmy W
07-13-2018, 09:30 PM
They said it was an effort to develop a 99% efficient gear train. The 1 or 2 percent improvement and maybe some weight savings probably won't make much real world difference, but it is an interesting experiment. As shown, it would probably be hard to sell a 13 speed set-up to folks that have been convinced that they need 22 gears and it would require a frame built just for the system.

Ed Harrow
07-13-2018, 10:53 PM
A derivative of the Metz transmission.

https://metzauto.files.wordpress.com/2009/06/1915-metz-model-25-30419-2.jpg

They just added 'teeth' for a better grip. :-)

Rob, yer just a kid. At my ancient and decrepit age I've had to go to a 42/24... Think of me on Sunday, 22 July, at the Major Taylor hill climb in Worcester.

Jimmy W
07-13-2018, 11:08 PM
A derivative of the Metz transmission.

https://metzauto.files.wordpress.com/2009/06/1915-metz-model-25-30419-2.jpg

They just added 'teeth' for a better grip. :-)



Yep.

https://i.ytimg.com/vi/VgHH_Tcufx4/hqdefault.jpg

Robbie 2
07-14-2018, 03:55 AM
How about further development for recumbents.
They might be able to replace that very long chain with a driveshaft sometime down the track.

Chris249
07-14-2018, 04:31 AM
There is a reason that after all this time we still use chains on “safety” bikes.

Quite simply, the bicycle drive train is as close to perfect as we can make anything work. It’s the best compromise between efficiency and strength going. So far...

Also, this drive for more gears boggles my mind. And huge cogwheels. I never had a gear larger than a 23 on a road bike (with a 42 front) or 28 on a mountain bike (and that with a 30 front, I never ran triples).

Then again, I’m a rouleur, and a flahute. I’m a masher. A grinder.

Also. Ceramic? Please. Just, no. No more ceramic on bikes, please. :)

Peace,
I Do Really Like Electronic Shifters, Though

Man, you either live in a flat area or REALLY like slow cadence!

Completely agree with your remarks about the lack of need for this system. There are some things - like the shape of the wheel itself - that are arguably already basically perfect already, and since the chain drive is one of the most efficient things in the world it seems like an odd place to search for improvements.

Paul Pless
07-14-2018, 04:46 AM
Man, you either live in a flat area or REALLY like slow cadence!or he's a total badass

LeeG
07-14-2018, 06:40 AM
I wonder what the q factor or pedal to pedal distance is?

David W Pratt
07-14-2018, 07:26 AM
Perhaps the deflection could be handled either by making it double shafted, one on each side, thus pushing against each other. Or, put the shifting in the bottom bracket, encased, oil bathed, clean and cozy. Pinion makes an 18 speed gearbox.
I'm guessing those cute ball bearing cogs can't handle much torque, or we would see them all over

amish rob
07-14-2018, 09:00 AM
Man, you either live in a flat area or REALLY like slow cadence!

Completely agree with your remarks about the lack of need for this system. There are some things - like the shape of the wheel itself - that are arguably already basically perfect already, and since the chain drive is one of the most efficient things in the world it seems like an odd place to search for improvements.

I would have guessed by rouleur and flahute that anyone would guess I am, indeed, a masher. Which I also called myself. The fact Iím shaped like Big Mig probably causes that, but Iím not sure. Long femurs.

As to hills? Heh. I live on the western edge of the Sierras. Which steep hill do you want to climb? :)

Peace,
Robert

P.S. Which doesnít mean I canít spin. I can maintain a smooth 120-130 for quite some time. The old school sit and spin sprints, and track racing taught me that skill.

amish rob
07-14-2018, 09:01 AM
I wonder what the q factor or pedal to pedal distance is?

Q factor? :)

This made my day.

Peace,
Robert

Ed Harrow
07-14-2018, 09:04 AM
Damn, you want 'slick', I'll show you slick!















https://barrtools.com/wp-content/uploads/2016/08/Slick-Scarf.jpg