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  #436  
Old 10-22-2020, 09:39 AM
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Velocipede Velocipede is offline
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Originally Posted by thirdgenbird View Post
I knew you were joking.

I think the “can’t be done” was to avoid the conversation above and is in the context of current hub width and chain spacing.

If cable pull matches, you probably could make 2x13 work if you made a longer b-link to clear the large cog and a longer cage to take up the extra chain required. The gap between derailleur and cassette would be far from idea however. Probably functional, but not to the standard of a top tier manufacturer.
But you can't make it work with the EKAR rear derailleur is the point. So you aren't making an EKAR 2x13. That's what I'm trying to get across. Which has always been the question or phrased as such.
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  #437  
Old 10-22-2020, 10:38 AM
thirdgenbird thirdgenbird is offline
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Absolutely. You could probably kludge it with a modified chorus derailleur but an Ekar derailleur is a non starter.
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  #438  
Old 10-22-2020, 11:23 AM
morrisond morrisond is offline
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Originally Posted by thirdgenbird View Post
We are not taking about different things. I provided reason to why keeping the ratio the same is not important to drivetrain designers. It also explains why a current chorus rd wouldn’t be ideal (or work at all) with a current ekar cassette. Narrowing the cassette range also diminishes the value of the added cog. Current 12spd cassettes are pretty tight with good range on 2x road applications. More range is compelling off-road, but then you have to start considering at the added benefit of 1x in those applications.

It also appear that ekar cantilevers the cassette further over the hub flange than 11 or 12 speed. Total speculation, but if this is the case, then it will limit the smallest size of the large cog. This is the same reason why shimano 11 “road” cassettes required a longer freehub but “gravel and mountain” versions fit on the shorter 8-10spd body. Combine this with the limits of slant parallelogram (see above) it could put usable cassette ranges somewhere between 11-36 and 11-45 based on systems with similar design restrictions. Not a typical offering for 2x road bikes. Cassettes that big often come with fat tires and rough surfaces. Fat tires and rough surfaces are compelling reasons to ditch the front derailleur. I recall seeing some Campagnolo patent applications that are focused at making derailleur travel non-liner so who knows what the future holds. Current state, Campagnolo has a fantastic 2x12 offering and what looks like a great 1x13 offering but mixing the two with known solutions would probably be a niche offering at best. All of this is probably what drove Campagnolo to say this:



Sure, it probably “could” be done, but it probably wouldn’t yield a product that is useful. A wider hub or thinner chain would would alter these restrictions, but then you are back to products not compatible with chorus 12 or ekar 13. These same limitations are probably how sram ended up with two totally different 12spd systems. They couldn’t fit their 12 speed mtb spacing into a traditional road application and they ended up with a cassette and chain spacing near identical to Campagnolo 12. Campagnolo used the extra space provided by the larger range cassette to add another cog. Sram may have done the same had they started with their road group and then moved to mtb.

All of this is to say derailleur ratio is pretty far down on the list of compatibility concerns. If it doesn’t match, it’s the easiest problem to fix in the aftermarket. If it does match, there are a number of reasons that would keep 2x13 from being a practical solution using existing Campagnolo hardware.

A road link only lets you clear a larger cog. Your b tension will be incorrect at the small end of the cassette. A fine hack in some cases.



Are you suggesting using an ekar derailleur in a 2x stystem?
No an Chorus one with a Road Link. Like I suggested far above and also mentioned that the existing EKAR cassettes could be a challenge without something like a Road Link with the best chance of working being an 9-36.

However this whole discussion started with my suggestion that Campy may easily be able to make it's existing Road Groups 2x13 as it appears as though the internal of an EKAR shifter (with the exception of 13 clicks) is the same as existing 12 sp.

Hence my suggestion Campy may just need to change the internals of Chorus/Record/SR shifters to EKAR - and get rid of the bar that restricts the EKAR thumb button (you would keep existing Chorus/R/SR thumb shifter) - have the CNC machines punch out new 11-29/11/32 13S speed cassettes and Voila you have 2x13. No change in rear Derailleur Geometry needed.

I would be stunned if they don't have prototypes already rolling around in testing and they could introduce it right after Shimano brings out 12sp Dura Ace.

EPS would be even easier and theoretically might be able to be back ported to 12s with a software change.

In the era of limited Campy budgets for limited R&D this would seem to be a no brainer - if it works.
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  #439  
Old 10-22-2020, 11:48 AM
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saab2000 saab2000 is offline
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Originally Posted by morrisond View Post

I would be stunned if they don't have prototypes already rolling around in testing and they could introduce it right after Shimano brings out 12sp Dura Ace.
This is totally plausible. 1x13 makes sense in the gravel bike universe but makes less sense for pure road riding. Wouldn’t surprise me at all to see 2x13 sooner rather than later.

When did Campagnolo first introduce 12-speed?
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  #440  
Old 10-22-2020, 12:25 PM
thirdgenbird thirdgenbird is offline
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Originally Posted by morrisond View Post
No change in rear Derailleur Geometry needed
If chorus geometry would have worked with Ekar cassettes, why did Campagnolo spend money changing it for Ekar? Why does shimano offer two totally different geometry xtr derailleurs? Why are sram road and mountain derailleurs totally different? It’s not strictly a 1x vs 2x design choice. The two different designs allow for different profile cassettes. The more range you cram into the same space, the more that profile changes.
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  #441  
Old 10-22-2020, 01:51 PM
morrisond morrisond is offline
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Quote:
Originally Posted by thirdgenbird View Post
If chorus geometry would have worked with Ekar cassettes, why did Campagnolo spend money changing it for Ekar? Why does shimano offer two totally different geometry xtr derailleurs? Why are sram road and mountain derailleurs totally different? It’s not strictly a 1x vs 2x design choice. The two different designs allow for different profile cassettes. The more range you cram into the same space, the more that profile changes.
Stop being an A** and taking things out of context as you continue to do.

That was referring to Chorus in a 2x system with an Cassette that is 13S with existing overall range which goes from 11/29-11/34 (I forgot that 11/34 can work with Record and SR).

You need a different geometry for 1x system as the difference between the big gear and small gear is usually a lot more than in an 2x system.

However if you think the RD would have to follow a different path in an 2x13s system that goes from 11 to 34 in the rear, vs 12s in the same amount of space - please enlighten us.
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  #442  
Old 10-22-2020, 02:11 PM
JWB475 JWB475 is offline
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Doesn't a typical 2x11 drivetrain already only have ~14 different gear ratios?

Honest question, what does 2x12, or 2x13 bring to the table other than even more duplicate gear ratios (and a really expensive cassette)?
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  #443  
Old 10-22-2020, 02:17 PM
joevers joevers is offline
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There's no 11-29 or 11-34 option. It's 9-36, 9-42, and 10-44. The point in previous pages is the limitations of a normal slant parallelogram derailleur like a Chorus one. The derailleur does follow a different path on something like an Ekar vs a Chorus one.

I'm sorry as maybe I missed a post or a point you're making but it seems like you're talking about using the Ekar cassettes and possibly shifters with an existing Chorus style derailleur and a road link and the point against that is that a Chorus derailleur with a road link absolutely does track differently.

It sounds like you're now backtracking and saying no, 2x13 totally would work it just needs a different derailleur, cassette, crankset, and shifter. Which... of course it would. But that's not the discussion.

There's no reason anything with Ekar needs to be compatible with anything from whatever hypothetical 2x13 group Campy may or may not release in the future. It's like being upset that the new Dura Ace which isn't even announced might not be compatible with the XT 12s 1x derailleurs. We don't know if they use the same pull, but they for sure use different cassettes and different derailleur geometries so it's not like they're compatible even if the pull is the same.
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  #444  
Old 10-22-2020, 02:24 PM
barnabyjones barnabyjones is offline
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These threads make me have deep thoughts while I ride. I had the following yesterday:

Would I miss a 17?
After 15 years of near competitive riding, do I know how to shift?
What is a slant parallelogram?
Why don't I shift into the small ring more often?
Math is fundamental.
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  #445  
Old 10-22-2020, 02:32 PM
thirdgenbird thirdgenbird is offline
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Quote:
Originally Posted by morrisond View Post
Stop being an A** and taking things out of context as you continue to do.

That was referring to Chorus in a 2x system with an Cassette that is 13S with existing overall range which goes from 11/29-11/34 (I forgot that 11/34 can work with Record and SR).

You need a different geometry for 1x system as the difference between the big gear and small gear is usually a lot more than in an 2x system.

However if you think the RD would have to follow a different path in an 2x13s system that goes from 11 to 34 in the rear, vs 12s in the same amount of space - please enlighten us.
This will be my last post as I thought it was a friendly conversation.

Per my earlier comments, I don’t think a 13spd 11-34 cassette would fit between the spokes and the dropout. I think Ekar (like other systems) has the large sprocket cantilevered over the hub flange and a 34 may not be large enough to fit. I think you need to go larger than 34 to make it fit with current chain widths creating a cassette that’s not very desirable for 2x drop bar bicycles.

Carry on...
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  #446  
Old 10-22-2020, 02:44 PM
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nighthawk nighthawk is offline
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Quote:
Originally Posted by thirdgenbird View Post
This will be my last post as I thought it was a friendly conversation.

Per my earlier comments, I don’t think a 13spd 11-34 cassette would fit between the spokes and the dropout. I think Ekar (like other systems) has the large sprocket cantilevered over the hub flange and a 34 may not be large enough to fit. I think you need to go larger than 34 to make it fit with current chain widths creating a cassette that’s not very desirable for 2x drop bar bicycles.

Carry on...
FWIW, I’ve appreciated your thoughts and sound logic on the subject. No reason for morrisond to take it personally and get bent out of shape. Just talking bike parts here.
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  #447  
Old 10-22-2020, 02:59 PM
tomato coupe tomato coupe is offline
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Quote:
Originally Posted by JWB475 View Post
Honest question, what does 2x12, or 2x13 bring to the table other than even more duplicate gear ratios (and a really expensive cassette)?
If the extra sprockets are added at the top or bottom of the cassette, then it obviously adds non-duplicate gears.
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  #448  
Old 10-22-2020, 03:36 PM
morrisond morrisond is offline
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Quote:
Originally Posted by thirdgenbird View Post
This will be my last post as I thought it was a friendly conversation.

Per my earlier comments, I don’t think a 13spd 11-34 cassette would fit between the spokes and the dropout. I think Ekar (like other systems) has the large sprocket cantilevered over the hub flange and a 34 may not be large enough to fit. I think you need to go larger than 34 to make it fit with current chain widths creating a cassette that’s not very desirable for 2x drop bar bicycles.

Carry on...
Sorry for the crack at you. I was getting frustrated.

People are making assumptions that it is cantilevered over the rear hub. Edit - yes according to Weenies 12s is slightly Cantilevered as well.

It may be or it may not - has anyone actually measured it? Given that we know the chain is .15mm thinner (actually according to this article it's .25mm skinnier - which gives you back 3mm https://cyclingmagazine.ca/gravel/ne...et-7-features/) it may not be or just ever so slightly over 12S.

That should be in the realm of the adjustability range on a current 2x12 rear derailleur.

Last edited by morrisond; 10-22-2020 at 04:10 PM. Reason: More information
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  #449  
Old 10-22-2020, 03:41 PM
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AngryScientist AngryScientist is offline
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Quote:
Originally Posted by morrisond View Post
Stop being an A** and taking things out of context as you continue to do.

That was referring to Chorus in a 2x system with an Cassette that is 13S with existing overall range which goes from 11/29-11/34 (I forgot that 11/34 can work with Record and SR).

You need a different geometry for 1x system as the difference between the big gear and small gear is usually a lot more than in an 2x system.

However if you think the RD would have to follow a different path in an 2x13s system that goes from 11 to 34 in the rear, vs 12s in the same amount of space - please enlighten us.

Infraction awarded. We’re talking about bike parts here. No need for personal attacks.
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  #450  
Old 10-22-2020, 03:46 PM
morrisond morrisond is offline
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Quote:
Originally Posted by joevers View Post
There's no 11-29 or 11-34 option. It's 9-36, 9-42, and 10-44. The point in previous pages is the limitations of a normal slant parallelogram derailleur like a Chorus one. The derailleur does follow a different path on something like an Ekar vs a Chorus one.

I'm sorry as maybe I missed a post or a point you're making but it seems like you're talking about using the Ekar cassettes and possibly shifters with an existing Chorus style derailleur and a road link and the point against that is that a Chorus derailleur with a road link absolutely does track differently.

It sounds like you're now backtracking and saying no, 2x13 totally would work it just needs a different derailleur, cassette, crankset, and shifter. Which... of course it would. But that's not the discussion.

There's no reason anything with Ekar needs to be compatible with anything from whatever hypothetical 2x13 group Campy may or may not release in the future. It's like being upset that the new Dura Ace which isn't even announced might not be compatible with the XT 12s 1x derailleurs. We don't know if they use the same pull, but they for sure use different cassettes and different derailleur geometries so it's not like they're compatible even if the pull is the same.
To start with I made two points - 2x13 might work with an 9-36 Cassette EKAR internals in an Chorus Right Shifter (or just use the Ekar right shifter) and an Road Link. Someone on here or on Velocipede got Chorus to work not badly with an SRAM 10-36 12S rear cassette. A road link might allow that combo to work better.

The other point I made is that it may be relatively easy for Campy to upgrade Chorus/Record/SR to 13s by swapping internals and making appropriate Cassettes. 11-29 13S with an 18 as the extra gear (nice straight block from 11-19) and maybe 11-34 13S which would be like 12S 11-29 with an extra gear. No new derailleurs needed as they are following the same path.
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