Login required to started new threads

Login required to post replies

Ceramic Speed DrivEn Concept - no more chains
Quote | Reply
https://cyclingtips.com/...d-driven-drivetrain/

Make Inside Out Sports your next online tri shop! http://www.insideoutsports.com/
Last edited by: BryanD: Jul 8, 18 1:00
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [BryanD] [ In reply to ]
Quote | Reply
Whoa.

I'm glad I was sitting down.

That's the most amazing thing I've seen on a bike in years. Innovation is not dead.

'It never gets easier, you just get crazier.'
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [georged] [ In reply to ]
Quote | Reply
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [BryanD] [ In reply to ]
Quote | Reply
That's easily the most innovative bike idea in the last ten years. I hope Ceramic Speed goes forward with it. I could even see how certain components, such as the cassette, would actually be less expensive to manufacture. My biggest concern is how only a couple of teeth on the front chainring are engaged at any given time... but I think that can be dealt with.

https://bikerumor.com/...-with-no-derailleur/
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [BryanD] [ In reply to ]
Quote | Reply
This looks incredible. If they pull it off, it would be the biggest innovation in cycling in decades. Getting the cartridge bearings on the shaft to shift smoothly between different gear ratios presents a challenge though. I wonder if it would work paired with some kind of CVT hub design or planetary gearing.
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [BryanD] [ In reply to ]
Quote | Reply
wow, this has to be the most positive post on ST ever?


have all the haters logged out?

-

http://www.thetrinerd.com
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [BryanD] [ In reply to ]
Quote | Reply

From an engineering standpoint, that's pretty cool. It'll be interesting to see how the development progresses.

http://bikeblather.blogspot.com/
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [Tom A.] [ In reply to ]
Quote | Reply
Tom A. wrote:

From an engineering standpoint, that's pretty cool. It'll be interesting to see how the development progresses.

I’m certainly no engineer, but my first thought was it would be tricky to eliminate flex in the system? This meet grinder could also have a nice aero cover to prevent injury quite easily.

_______________________________________________
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [BryanD] [ In reply to ]
Quote | Reply
Side note: I really like the raised drive-side chainstay. It might not be aesthetically perfect but it would make for quicker and easier rear wheel changes and flat repairs.


Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [GreenPlease] [ In reply to ]
Quote | Reply
Yeah, it seems like rear wheel changes would be less of a pita. Plus I’d save lots of time not cleaning and lubing my chain!

Matt
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [BryanD] [ In reply to ]
Quote | Reply
Wow if they can get this to work.......amazing!!!

"see the world as it is not as you want it to be"
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [TizzleDK] [ In reply to ]
Quote | Reply
TizzleDK wrote:
Wow if they can get this to work.......amazing!!!

I stopped reading when I got to "it doesn't actually work" ...
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [spntrxi] [ In reply to ]
Quote | Reply
Every product goes through that phase at some point though. And it does work from the sound of it, just only as a singlespeed which is more than i thought they'd have when i started reading the article.
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [spntrxi] [ In reply to ]
Quote | Reply
It certainly will work as a single speed.

I look at this as really cool concept, we will see if it goes further. It certainly would need to gain interest from one of the big players to make it happen. So much so, this maybe an idea that gets ceramic speed scooped up by someone else in order to preserve the patent.

Now, on the engineering side. With wireless technology available now, I can see this working. Put a clutch mechanism on the hub similar to where the free hub sits now. This would allow for the gear to move out of the way. A wireless mechanism to move the drive sprocket and you are in business. That is easier said then done, but the mechanics would be pretty simple. From a force standpoint, and without doing any math behind the subject, it appears their gear design will not work very well and have the longevity that would be desired. The cross section of contact will simply be too small.

The other risk to this design is cost. Sprockets are likely very very cheap to make. Chains are cheap to make. Gears on the other hand are not and I believe to make this work correctly they will need to go to a gear design instead of what they have shown.
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [BryanD] [ In reply to ]
Quote | Reply
so all the national track federations are calling ceramic speed to integrate this into their track bikes for the 2020 olympics, right?

Amateur recreational hobbyist cyclist
https://www.strava.com/athletes/337152
https://vimeo.com/user11846099
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [BryanD] [ In reply to ]
Quote | Reply
Hi Bryan,

Thanks for sharing.

It’s been a busy day here at Eurobike and now it’s time for a beer :)

The system, whilst early in our development, is trustworthy in terms of real world use.

I’ll keep an eye on the forum and drop in when possible.

Ben

Chief Marketing Officer,
CeramicSpeed
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [BryanD] [ In reply to ]
Quote | Reply
Very cool. Although some thought the disc brakes would cut you up pretty bad...
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [BPowell_CS] [ In reply to ]
Quote | Reply
BPowell_CS wrote:
Hi Bryan,

Thanks for sharing.

It’s been a busy day here at Eurobike and now it’s time for a beer :)

The system, whilst early in our development, is trustworthy in terms of real world use.

I’ll keep an eye on the forum and drop in when possible.

Ben

At first glance, this looks very cool but I see a lot of problems to make this work.
1) chain system is so simple and works so great and is cheap that it will be difficult to get people to convert.
2) other manufacturers may not want to play nice. Looks like frames have to be redisgned and gearing components may need to be redesigned. I am not sure if the other companies would accommodate for the changes. After all redesigning and testing costs money.
3) cost. Even if it becomes a realistic option, I am asking if I would spend an extra $1000 and be limited with aftermarket components? I am not sure.

the concept is very cool indeed, but it reminds me of those concept cars at auto shows where you see a cool car that doesn’t come to fruition.
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [KingMidas] [ In reply to ]
Quote | Reply
KingMidas wrote:
BPowell_CS wrote:
Hi Bryan,

Thanks for sharing.

It’s been a busy day here at Eurobike and now it’s time for a beer :)

The system, whilst early in our development, is trustworthy in terms of real world use.

I’ll keep an eye on the forum and drop in when possible.

Ben


At first glance, this looks very cool but I see a lot of problems to make this work.
1) chain system is so simple and works so great and is cheap that it will be difficult to get people to convert.
2) other manufacturers may not want to play nice. Looks like frames have to be redisgned and gearing components may need to be redesigned. I am not sure if the other companies would accommodate for the changes. After all redesigning and testing costs money.
3) cost. Even if it becomes a realistic option, I am asking if I would spend an extra $1000 and be limited with aftermarket components? I am not sure.

the concept is very cool indeed, but it reminds me of those concept cars at auto shows where you see a cool car that doesn’t come to fruition.

If you move to a true gear design, you don't need a different frame. Simply use the derailleur mount to mount the end of the shaft, you don't need to be on the center line of the wheel with a gear. Bike design becomes much less critical.
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [BryanD] [ In reply to ]
Quote | Reply
You could make it shift by using a spline shaft, and sliding the hub with the rollers to slide back and forth on the shaft to engage different sprockets. By attaching a secondary hub to the hub with the rollers, you could operate the shifting with a cable and spring, like current mechanical derailleurs. The biggest difficulty lies in the fact that the sprockets are aligned in only one position; there is only one point you could slide from one sprocket to another. This could be overcome by allowing the rollers to completely disengage from one sprocket before engaging with the next sprocket.
Not sure I like the unsealed bearings, but they are going for minimum friction on this prototype, so that is OK. A more practical device may use bushings (like a chain and some derailleurs do now) but there would be a friction penalty. But this is still early in the development cycle. Looks very cool.

salmon - not because I'm a fish
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [GreenPlease] [ In reply to ]
Quote | Reply
GreenPlease wrote:
That's easily the most innovative bike idea in the last ten years. I hope Ceramic Speed goes forward with it. I could even see how certain components, such as the cassette, would actually be less expensive to manufacture. My biggest concern is how only a couple of teeth on the front chainring are engaged at any given time... but I think that can be dealt with.

https://bikerumor.com/...-with-no-derailleur/

What's really interesting (to me, at least) is that the interfaces are basically the same as a chain roller/tooth interface...just turned 90 degrees so that you can fit a roller bearing inside the roller.

In other words, you could do the same thing with a chain, if you just fit miniature ball (watch) bearings into each of the chain rollers so it didn't have a sliding interface on the inside of the roller against the chain pins. That would make for quite the expensive chain, though...then again, it would last quite a bit longer than a regular chain.

I find it interesting that everyone immediately jumps to some sort of wireless activation of the shifting mechanism. How about just add another external bearing (there's already a gajillion in the thing...what's one more?) on the movable shaft and just manually move it back and forth externally...sort of like the throwout bearing on an automobile clutch? One could do it with a cable, or electronically...even hydraulically.

Also, there's one thing that might cause some of the main drivetrain players (i.e. Shimano, Sram, Campy) to not want to license this...it removes a steady revenue stream from a "consumable" item ;-)

http://bikeblather.blogspot.com/
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [Tom A.] [ In reply to ]
Quote | Reply
Pretty sure that's already on a campy crank ?

But as the logos have been flatted back perhaps they don't know about it yet ... lol

WD :-)
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [Tom A.] [ In reply to ]
Quote | Reply
Alternately the “bevel gear†could be contoured in such a way to encourage shifts (e.g. “fall†onto the next gear, with every other “tooth†being contoured an opposite direction).
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [BryanD] [ In reply to ]
Quote | Reply
'90s technology at its finest.

.
.
.
.
..
.
1890s that is...
https://en.wikipedia.org/wiki/Shaft-driven_bicycle
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [Tom A.] [ In reply to ]
Quote | Reply
In this video they describe how the shifting will work:
https://www.youtube.com/...amp;feature=youtu.be


It's a pretty interesting idea. Lots of people have tried to improve on the mechanical efficiency of a traditional chain drive system for a long time without practical success. It's really very efficient to begin with. I'd be interested in seeing an independent test. How do they deal with the concentric shaft friction? Are there roller bearings in there too?

I'll also be interested in how fast that shifting can happen. To make that work they are going to have to get an encoder in there somewhere. Maybe in the parabolic shifting channel it will be able to span the whole range of gears within one revolution, but that servo motor will have to be awfully fast. Like really fast.

I wonder how much this will cost....

Your idea about incorporating watch bearings into a conventional chain is interesting, but they would have to be such small diameters, I wonder if hertz stresses would be a deal killer, even at the relatively low loads involved in cycling.

-------------
Ed O'Malley
www.VeloVetta.com
Founder of VeloVetta Cycling Shoes
Instagram • Facebook
Last edited by: RowToTri: Jul 10, 18 11:25
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [RowToTri] [ In reply to ]
Quote | Reply
I also wonder about the "feel" of this system and the tourque associated with putting power down. Anyone who's ridden a motorbike with a shaft drive will tell you that you can really feel the bike's frame twisted and pulling to one side when you put the power down.

Maybe not an issue for a commuter bike but for a performance bike you definitely would't want this.
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [TriNewbieZA] [ In reply to ]
Quote | Reply
  
looks a bit like this :




I cant imagine how the drive shaft might move to shift gears on the ceramic speed one

The big difference is a normal drivetrain the chain is spread over at least 6 teeth at any one time - here the maximum is 2 or so - so the force on the teeth is massively more - so teeth have to be much stronger


looks beautiful though - very nice concept art
Last edited by: lacticturkey: Jul 11, 18 5:46
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [lacticturkey] [ In reply to ]
Quote | Reply
It would be additionally interesting if it was possible to put another internal gear in the shaft so that you could turn it into a something like a 39 speed. Think old sturmey archer internal gear inside the shaft to multiply the rotation ratio. That would be super cool.
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [KingMidas] [ In reply to ]
Quote | Reply
KingMidas wrote:
BPowell_CS wrote:
Hi Bryan,

Thanks for sharing.

It’s been a busy day here at Eurobike and now it’s time for a beer :)

The system, whilst early in our development, is trustworthy in terms of real world use.

I’ll keep an eye on the forum and drop in when possible.

Ben


At first glance, this looks very cool but I see a lot of problems to make this work.
1) chain system is so simple and works so great and is cheap that it will be difficult to get people to convert.
2) other manufacturers may not want to play nice. Looks like frames have to be redisgned and gearing components may need to be redesigned. I am not sure if the other companies would accommodate for the changes. After all redesigning and testing costs money.
3) cost. Even if it becomes a realistic option, I am asking if I would spend an extra $1000 and be limited with aftermarket components? I am not sure.

the concept is very cool indeed, but it reminds me of those concept cars at auto shows where you see a cool car that doesn’t come to fruition.


I think you are wrong, look how all basic mountain bike standards such as freehub design, hub spacing (boost), 1X, frame redesign to has happened in the last 3 years to accomodate for 1X drivetrains for MTB. Shimano just released their new freehub body for XTR that was their first change to the standard in 30 years. Companies are willing to change standards if the benefits are big enough. The bike companies are falling all over themselves to find a compelling reason to innovate and upgrade their customers. Business 101. Cost will start high but become lower over time, as always.
Last edited by: endosch2: Jul 11, 18 6:37
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [lacticturkey] [ In reply to ]
Quote | Reply
lacticturkey wrote:



looks beautiful though - very nice concept art



It's way past the art stage. Getting to the point of fabricating functional roller/tooth interfaces, even at very low torque, took an engineer, not an artist.

I don't think they've figured out functional shifting yet, though. That'll be a neat trick.


Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [lacticturkey] [ In reply to ]
Quote | Reply
lacticturkey wrote:

looks a bit like this :




I cant imagine how the drive shaft might move to shift gears on the ceramic speed one

The big difference is a normal drivetrain the chain is spread over at least 6 teeth at any one time - here the maximum is 2 or so - so the force on the teeth is massively more - so teeth have to be much stronger


looks beautiful though - very nice concept art

Steel should be a viable fix for the front chainring.
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [GreenPlease] [ In reply to ]
Quote | Reply
The pic link didnt work before :



Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [RowToTri] [ In reply to ]
Quote | Reply
RowToTri wrote:
Your idea about incorporating watch bearings into a conventional chain is interesting, but they would have to be such small diameters, I wonder if hertz stresses would be a deal killer, even at the relatively low loads involved in cycling.

Yeah...would probably need to be at least roller bearings instead of ball to handle the loads...Of course, I didn't say the idea was practical though, did I? ;-)

http://bikeblather.blogspot.com/
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [lacticturkey] [ In reply to ]
Quote | Reply
lacticturkey wrote:
The pic link didnt work before :



Bevel gear efficiencies max out around 97%. Also they are pretty limited in gear ratios and I think efficiencies go down as you increase the ratio.

Better materials, electronics, computing power, etc can take a basic idea that was not that great 100 years ago and make it great today.

-------------
Ed O'Malley
www.VeloVetta.com
Founder of VeloVetta Cycling Shoes
Instagram • Facebook
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [RowToTri] [ In reply to ]
Quote | Reply
i couldnt find this pic whent he thread first poped up,
Last edited by: JRC: Jul 16, 18 1:25
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [trail] [ In reply to ]
Quote | Reply
For sure the shifting will be interesting... in the one vid they mention the two channels on the rear cassette with two shifting areas. The big question is how do they propose to move the rear bearing assembly to change gears?

Some sort of indexing mixed with electronics or ??? It is an interesting development.
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [xeon] [ In reply to ]
Quote | Reply
xeon wrote:
For sure the shifting will be interesting... in the one vid they mention the two channels on the rear cassette with two shifting areas. The big question is how do they propose to move the rear bearing assembly to change gears?

Yeah, all sort of complications with clutches, alignment, allowing the rider to still pedal while that's all going on (or not) . Super interesting engineering problem.
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [BryanD] [ In reply to ]
Quote | Reply
All that, and aero, too!

I would love to see them Proof of Concept this on a track bike.
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [shoff14] [ In reply to ]
Quote | Reply
shoff14 wrote:
From a force standpoint, and without doing any math behind the subject, it appears their gear design will not work very well and have the longevity that would be desired. The cross section of contact will simply be too small.


Yeah, I was thinking something similar.

It is a cool concept so far though.

https://www.strava.com/...tes/zachary_mckinney
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [plant_based] [ In reply to ]
Quote | Reply
in tems of the gear shifting, one way i could see it working is,

you measure the speed and position of the rear "cassette", and allocate windows for the bearing assy to move to the next location, this should not be too hard as its pretty similar to the way engine management looks at the crank and gets the spark in the correct position. I think the real problem is getting it to do it reliably under load, maybe the bearing assy could be fired from one slot to the next quickly enough, but I'd be supprised, maybe a system that only changes under no load or the casset rotating slower than the wheel?

Also m wondering what ratio's can be accomodated, obviosly there is a limit to how close the cassette "rings" can be together, i wonder what change in teeth this is, probably not likly that an 11-22 straight up could be done.
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [BryanD] [ In reply to ]
Quote | Reply
https://www.youtube.com/watch?v=AQIfNygVMDE

According to GCN seems they've actually sold one of these in Dubai.
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [BryanD] [ In reply to ]
Quote | Reply
Talk to me when it shifts, until then it's vaporware
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [jhammond] [ In reply to ]
Quote | Reply
Ya'll are a bunch of pessimistic haters

https://www.youtube.com/watch?v=bmEYfdZOGAc
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [jhammond] [ In reply to ]
Quote | Reply
jhammond wrote:
Talk to me when it shifts, until then it's vaporware

Not vaporware. It's a track bike.
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [trail] [ In reply to ]
Quote | Reply
trail wrote:
jhammond wrote:
Talk to me when it shifts, until then it's vaporware


Not vaporware. It's a track bike.
Until I see a person riding it and applying a high torque, it's not even that...
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [Benv] [ In reply to ]
Quote | Reply
Benv wrote:
trail wrote:
jhammond wrote:
Talk to me when it shifts, until then it's vaporware


Not vaporware. It's a track bike.
Until I see a person riding it and applying a high torque, it's not even that...


So many haters.

CS, "Here's an early prototype. Nowhere near a product yet."

ST, "It's just a prototype, not anywhere near to being a product.". Well duh.
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [trail] [ In reply to ]
Quote | Reply
trail wrote:
Benv wrote:
trail wrote:
jhammond wrote:
Talk to me when it shifts, until then it's vaporware


Not vaporware. It's a track bike.
Until I see a person riding it and applying a high torque, it's not even that...



So many haters.

CS, "Here's an early prototype. Nowhere near a product yet."

ST, "It's just a prototype, not anywhere near to being a product.". Well duh.
I don't agree with you. It's more like this:

CS: "we intented the best drive train ever! Only 1 watt!"
ST: "does it shift and does it work under load?"
CS: "It's the most aero too!"
ST: "But does it shift and does it work under load?"
CS: (silence)
CS: "But we also have an aero cover for it!"
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [Benv] [ In reply to ]
Quote | Reply
Looks like it also can't be retrofit to an existing bike...

Strava
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [gmh39] [ In reply to ]
Quote | Reply
gmh39 wrote:
Looks like it also can't be retrofit to an existing bike...

Therefore no manufacturer will implement it due to having to have a custom frame. It's a great marketing ad though!

Make Inside Out Sports your next online tri shop! http://www.insideoutsports.com/
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [BryanD] [ In reply to ]
Quote | Reply
Well there is the possibility of future frames being compatible (similar to how frames can be di2 and mach compatible). But that just lengthens any kind of adoption timeline.

Strava
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [gmh39] [ In reply to ]
Quote | Reply
The frame requirements will kill this, if everything else that is awful about it doesn't.
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [Benv] [ In reply to ]
Quote | Reply
Benv wrote:
ST: "But does it shift and does it work under load?"

Well they showed how it can shift, and is seems plausible.

And I understand the concern about torque/force getting concentrated on just 1-2 rollers vs the load-spreading of a chain. But I don't understand the notion in this thread that it's like this really confounding problem to material science and mechanical engineering. Humans aren't *that* strong, even with the leverage of a crank arm/pinion. And steel is really, really strong.

It's plausibly efficient. And I really like that it can be protected and kept clean, vs. chains which are always in the process of getting dirty when ridden.

I'm much more interested in this thing than the oversized pulley wheel stuff - or really anything else that CeramicSpeed does.

Might be 4-5 years, but I'm hoping it works out.
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [trail] [ In reply to ]
Quote | Reply
I have not seen a video of a system that even had pedals on it and was subject to the forces at play when someone rides a bike and the bike deflects under varying load.

I have also not seen a video that demonstrated shifting across the entire cassette (just one gear in the middle). And oh yeah the model with shifting was different from the one in all the pretty pictures.

It supposedly uses a motor but even that is about all they’ll say because they haven’t quite figured it out yet.
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [trail] [ In reply to ]
Quote | Reply
Exactly, there is no problem for steel to withstand our small legs strength even on a reduced contact point.There might be some wear problem for sure.
It also looks like it will cost a ton of money. Precision machining, electronics for shifting. CeramicSpeed being used to sell thing 10x their value, i expect them to market this thing above 5K. That said it won't be incredibly better than a regular drivetrain because a clean well lubed drivetrain is already very efficient, not much to win here. I expect the weight to be crazy low which might be a bit frustrating for events with a lot of climbing, mountain biking. It would sound a bit like an unfair advantage (remember the frustration of shimano pro XC racer when they had no good 1X option)
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [trail] [ In reply to ]
Quote | Reply
trail wrote:
Benv wrote:

ST: "But does it shift and does it work under load?"


Well they showed how it can shift, and is seems plausible.
Plausible != good. Demonstrating it under no load at maybe 30 rpm doesn't convince me it's a good idea that would work at 1500W and 120 rpm.
Don't get me wrong, the shifting mechanism is ingenious, but horrendously complicated and at high risk of spectacular failure.

Quote:
And I understand the concern about torque/force getting concentrated on just 1-2 rollers vs the load-spreading of a chain. But I don't understand the notion in this thread that it's like this really confounding problem to material science and mechanical engineering. Humans aren't *that* strong, even with the leverage of a crank arm/pinion. And steel is really, really strong.

A back of the envelope calculation of the force an average rider standing on the cranks would put through a single deep groove ball bearing gives a number well in excess of the C0 (static load rating) of the size of bearings they're using. That's for bearings that have had decades of material science and manufacturing technology development. Steel is strong, sure, but the point loads will kill it. Humans don't output lots of power, but due to the low speeds we can output extremely high torque. A big chunk of steel would do it (as has been proven with bevel gear shaft drive bikes), but not a ball bearing system.

Quote:
It's plausibly efficient. And I really like that it can be protected and kept clean, vs. chains which are always in the process of getting dirty when ridden.
I disagree with the efficiency claims, there are still sliding faces in contact. And it would be just as feasible (and race-illegal) to put a cover over a derailleur chain system to protect it.
Last edited by: MattyK: Sep 6, 19 5:30
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [MattyK] [ In reply to ]
Quote | Reply
It's a marketing video to get people interested in Ceramic Speed again. While interesting, I doubt it will ever come to market. If it does, it will be on a custom frame that will be very expensive.

Make Inside Out Sports your next online tri shop! http://www.insideoutsports.com/
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [BryanD] [ In reply to ]
Quote | Reply
BryanD wrote:
It's a marketing video to get people interested in Ceramic Speed again. While interesting, I doubt it will ever come to market. If it does, it will be on a custom frame that will be very expensive.
100%. They are certainly getting value for money out of the gullible media
Quote Reply
Re: Ceramic Speed DrivEn Concept - no more chains [MattyK] [ In reply to ]
Quote | Reply
Yep.
Give it to me on a moutain bike for this coming autumn and winter.
I'm confident that in the part of the world I live I'll have turned the bike into a very expensive seized up hobby horse not far out of the car park.
Quote Reply