Update old crankset with 11 speed chainrings?

[NHAero]

Can my old Sugino AT cranks work with 11 speed STI shifters if I update with 11 speed chainrings? Or has the spacing changed? Currently running 48-36-24 9 speed rings.
Thanks!

[ultraman6970]

IME the only way to know is just swap the chain for an 11 speed chain. Big chances that it will work fine. But since is shimano... I have no idea how it will work. Campagnolo uses a ratchet for the FD, and that makes a big difference when you have to do weird stuff because you can trim that at will.

[Kontact]

It will work with your current chainrings. There is no real difference in chainring spacing since 5 speed bikes.

If you want increased performance, buy some sort of large chainring with lifter ramps if your current large chainring doesn't have them. 8, 9, 10 speed rings will all work fine.

http://www.velonews.com/2015/03/bike...ibility_362722

[NHAero]

Very helpful, thanks!

Originally Posted by Kontact

It will work with your current chainrings. There is no real difference in chainring spacing since 5 speed bikes.

If you want increased performance, buy some sort of large chainring with lifter ramps if your current large chainring doesn't have them. 8, 9, 10 speed rings will all work fine.

http://www.velonews.com/2015/03/bike...ibility_362722

[11.4]

It may be a bit better, but you aren't getting everything you get with modern equipment overall. Your gears are small so there won't be much in the way of pins and ramps to support your shifting. However, your bigger rings won't be as stiff as the newer hollow rings you find on Dura Ace or Ultegra. Those are why Shimano front shifters overwhelm everything else in the market.

You may also find that because 11-speed cranksets have those fatter large chainrings, there's more spacing between their centerlines. If you put an 11-speed chain on your new 11-speed chainrings, you may find the chain will ride on the top of the smaller rings and not drop in quite as nicely.

Last, remember that BCDs and spider arrangements have changed for newer 11-speed chainrings, and tooth combinations have decreased. You may not find something to fit your current crank the way you want.

[Kontact]

But you don't need 11 speed specific rings to get good shifting with an 11 speed chain. Put a thoroughly modern 10 speed large chainring on and it will shift great.

11 speed has been with us for 9 years. All of these experiments have been tried long ago.

[oldpotatoe]

Originally Posted by NHAero

Can my old Sugino AT cranks work with 11 speed STI shifters if I update with 11 speed chainrings? Or has the spacing changed? Currently running 48-36-24 9 speed rings.
Thanks!

11s rings are a wee bit closer together..Chances are, with STI, it'll be fine. You 'may' get some chain to fder rub at highest or lowest geasr but I think'll they will be fine. Lots of CRs are labeled, 10/11 anyway.

Pic on left is 9s CR from Campag, right one is 10s CR, and how they removed some material to get the rings closer together..NOT the same spacing since 5s days...

[dddd]

Shimano's chainring spacing has actually become wider over the years, due to the profiling of the back side of the big ring, which keeps the chain from possibly falling to the right side of the small ring's teeth.
The profiling and wider spacing better controls the chain during downshifts, accommodating the tendency of the barely-tensioned upper run of the chain to bow inward as the chain falls to a smaller ring.

But, at least with their 5-arm cranksets, it is the small ring that determines the chain width that is suitable for the pair of chainrings, so for example, one can replace the small ring on a 9-speed crankset to make it more compatible with 10s chain, or vice-versa. There are Shimano "B-series" 39t chainrings available for properly converting their 8 and 9s and cranksets to 10s.

Campagnolo's 5-arm cranksets alternately use differing big rings to determine the chainring pair's compatibility with the chain's width, hence you'll see big rings with "10 Speed" printed on them, though it appears that perhaps nothing changed there when they rolled out 9s grouppos.

With MTB's now using very compact or single-chainring options, I don't know of any 110/74mm triple-chainring sets made for 11s use with the OP's chainring sizes, but perhaps 10s rings could be sourced that would likely shift well with an 11s chain. The Shimano rings aren't cheap though, so it might actually be cheaper in this case to find and buy one of their 10s trekking cranksets from an online discount retailer.

[Kontact]

Originally Posted by oldpotatoe

11s rings are a wee bit closer together..Chances are, with STI, it'll be fine. You 'may' get some chain to fder rub at highest or lowest geasr but I think'll they will be fine. Lots of CRs are labeled, 10/11 anyway.

Pic on left is 9s CR from Campag, right one is 10s CR, and how they removed some material to get the rings closer together..NOT the same spacing since 5s days...

That's only .25mm narrower for Campy. And it got slightly wider for Shimano and SRAM (SRAM spacing increased for cross chaining clearance). If you buy a Rotor crank it stayed the same.

I think it is unwise to interpret the minuscule variations in chainring spacing as having to do with chain compatibility rather than refinements to specific chainring's shifting action or cross chaining. 11 speed chains are all the same inner and outer width, so Shimano and SRAM going wider while Campy narrowed all with the same chain means that there is no real issue.


My personal experience is that the front derailleur design has more to do with great front shifting than the difference between one pinned chainring and another.

I would definitely breath life into a lovely old Sugino crank with a modern 9/10/11 speed outer ring and ride with confidence. Just make sure you get a chainring with a drop pin behind the crankarm if the original chainring had one.

[dddd]

Originally Posted by Kontact

...I think it is unwise to interpret the minuscule variations in chainring spacing as having to do with chain compatibility rather than refinements to specific chainring's shifting action or cross chaining. 11 speed chains are all the same inner and outer width, so Shimano and SRAM going wider while Campy narrowed all with the same chain means that there is no real issue...

I think that you might have missed my point about the chainring spacing not being just about where the teeth are.
With the more or less cone-shaped inner profile of Shimano's big rings from the recent 10s and 11s era, the critical spacing becomes more about the spacing between the small ring's teeth and the smooth inner face of the big ring than how far out that the big ring's teeth are spaced from the small ring. The inner and outer ring's teeth are spaced further apart, but the narrower chain is still guided tightly by the inner face of the big ring as it falls onto the small chainring during a downshift.

And yes, the spacing was also increased to provide greater cross-chaining clearance for the larger 16t size difference between rings on typical newer compact cranksets.

Often, but not always, a minor change in chain width is well tolerated by an existing crankset, but I've also seen cases where even the correct chain managed to eventually cut a step into the tips of the small ring's teeth, which a narrower chain would be only more likely to cause.

Minor corrections to the effective chainring spacing as measured at the tips of the small ring's teeth can be effected by turning the cranks with a file held against one side of the small ring's teeth at a beveling angle. This won't be effective with the big ring though, and holding the file in the right spot while keeping your hand and arm out of the way of the turning cranks must be done carefully.
I often use this as a final step after correcting any bent inner chainring or teeth, but it can also be used to better accommodate a narrower chain with respect to downshift engagement. This process can also be used to correct the above-mentioned notch wear of a small chainring's teeth.

Picture below illustrates the positioning of the file while the cranks are turned, but either side of the small ring's teeth can be beveled slightly depending on the needs of the moment. In this case I was correcting a tendency for the 9s chain to fall to the inside of the 9s small ring's teeth during downshifts, and the bike is no longer dropping it's chain. Often it is just small burrs or other invisible damage to the tips of the teeth that causes the chain to suddenly start preferring to drop to one side or the other instead of centered on the teeth, so only a trace(!) of metal needs to be removed to make the chain engage reliably.
I've modified many vintage bike chainrings over the years using similar methods to accommodate narrower modern chain, in part because in many cases there will be no newer chanrings available to fit a vintage crankset's bolt circle configuraton.

[Kontact]

Originally Posted by dddd

I think that you might have missed my point about the chainring spacing not being just about where the teeth are.
With the more or less cone-shaped inner profile of Shimano's big rings from the recent 10s and 11s era, the critical spacing becomes more about the spacing between the small ring's teeth and the smooth inner face of the big ring than how far out that the big ring's teeth are spaced from the small ring. The inner and outer ring's teeth are spaced further apart, but the narrower chain is still guided tightly by the inner face of the big ring as it falls onto the small chainring during a downshift.

And yes, the spacing was also increased to provide greater cross-chaining clearance for the larger 16t size difference between rings on typical newer compact cranksets.

Often, but not always, a minor change in chain width is well tolerated by an existing crankset, but I've also seen cases where even the correct chain managed to eventually cut a step into the tips of the small ring's teeth, which a narrower chain would be only more likely to cause.

Minor corrections to the effective chainring spacing as measured at the tips of the small ring's teeth can be effected by turning the cranks with a file held against one side of the small ring's teeth at a beveling angle. This won't be effective with the big ring though, and holding the file in the right spot while keeping your hand and arm out of the way of the turning cranks must be done carefully.
I often use this as a final step after correcting any bent inner chainring or teeth, but it can also be used to better accommodate a narrower chain with respect to downshift engagement. This process can also be used to correct the above-mentioned notch wear of a small chainring's teeth.

Picture below illustrates the positioning of the file while the cranks are turned, but either side of the small ring's teeth can be beveled slightly depending on the needs of the moment. In this case I was correcting a tendency for the 9s chain to fall to the inside of the 9s small ring's teeth during downshifts, and the bike is no longer dropping it's chain. Often it is just small burrs or other invisible damage to the tips of the teeth that causes the chain to suddenly start preferring to drop to one side or the other instead of centered on the teeth, so only a trace(!) of metal needs to be removed to make the chain engage reliably.
I've modified many vintage bike chainrings over the years using similar methods to accommodate narrower modern chain, in part because in many cases there will be no newer chanrings available to fit a vintage crankset's bolt circle configuraton.

It isn't that I missed your point, I simply don't see the relevance considering that the Shimano 4 hole rings won't mount on a Sugino crank.

The only question we need to ask ourselves is if a 9/10 speed crank will work with an 11 speed chain. The point I was making is that the breadth of 11 speed cranks have more, less and the same spacing as 10, which suggests that the variation isn't critically important to work with a 11 speed chain and the variations are only there to service specific design goals of each crank.

[dddd]

I did say "from the 10s and 11s era", and the 10s ones are 110mm 5-arm, but some of the comments from earlier seemed to be referring to typical compact doubles.
Shimano's road triples never came offered with a 110mm bolt pattern.

And of course Shimano never made "a 9/10 speed crank", but I don't think that you intended to say that they did.

But I guess more importantly, the OP is running a triple of specified ring sizes, so unless he wants to test out using a 9s or 10s Trekking crank's rings on the AT crankarms, he might end up having to buy aftermarket rings singly. I mentioned the Trekking cranks for the specific rings that they come with, because these entire cranksets seem to occasionally turn up at a lower price than what the rings might sell for, and I have a personal preference for matched sets of Shimano rings.

I believe that the AT crank's spider tabs are of equivalent thickness to modern 5-arm Shimano. The granny ring's position happens to be held by means of removable spacers on the AT crank, so that at least allows the 1-2 ring spacing to be tailored as needed.

I wouldn't rule out that the existing 9s rings might work perfectly with the 11s chain, but I would be fully prepared to file slightly, and if necessary even bend the smaller ring's teeth outward toward the bigger ring as needed. I've done this using both methods and have found it easy to bend the teeth slightly using an adjustable wrench, but the rings will need to removed for any tooth-bending session.

[Kontact]

Originally Posted by dddd

I did say "from the 10s and 11s era", and the 10s ones are 110mm 5-arm, but some of the comments from earlier seemed to be referring to typical compact doubles.
Shimano's road triples never came offered with a 110mm bolt pattern.

And of course Shimano never made "a 9/10 speed crank", but I don't think that you intended to say that they did.

But I guess more importantly, the OP is running a triple of specified ring sizes, so unless he wants to test out using a 9s or 10s Trekking crank's rings on the AT crankarms, he might end up having to buy aftermarket rings singly. I mentioned the Trekking cranks for the specific rings that they come with, because these entire cranksets seem to occasionally turn up at a lower price than what the rings might sell for, and I have a personal preference for matched sets of Shimano rings.

I believe that the AT crank's spider tabs are of equivalent thickness to modern 5-arm Shimano. The granny ring's position happens to be held by means of removable spacers on the AT crank, so that at least allows the 1-2 ring spacing to be tailored as needed.

I wouldn't rule out that the existing 9s rings might work perfectly with the 11s chain, but I would be fully prepared to file slightly, and if necessary even bend the smaller ring's teeth outward toward the bigger ring as needed. I've done this using both methods and have found it easy to bend the teeth slightly using an adjustable wrench, but the rings will need to removed for any tooth-bending session.

The whole world isn't Shimano. I said 9/10 because there are non-Shimano cranks that bridged 9 to 10, just like there are now cranks that work for 10 and 11. It is little different from how there was never really a "9 speed" rear derailleur.



Going back to the OP, there are no triple 11 speed shifters, but you can mix the shifters between 3x10 and 2x11. I don't know if the OP is planning on keeping his triple or dropping the small ring, but if he's just keeping the gearing he has, 9 speed lifter rings are not different from 10. Leave the rings and use them. And that shouldn't require filing anything. I would be floored if the OPs current set up didn't work.

[NHAero]

dddd and Kontact, thanks for sharing your understanding and experience. Here in more detail is what I'm trying to accomplish:

I'd like to switch my Anderson from bar end shifting to integrated STI shifting, and I want to retain hydro discs (using TRP Hylex now). That seems to push towards the 11 speed world, with the RS685 shifters and the RS785 calipers. With 11 speed, I could get almost all of the gear range I have now with 2x11. I've been running TA Zephyr 9/10 speed rings for the 48T and 36T. I have a tab mount for the fd so I can't lower the fd much more, so I'm kind of stuck with the 48T as the smallest outer ring. I run that now with a 13T small sprocket giving a 101 inch gear with the 37-622 tires. I'm looking into whether I can build a 13-34 11 speed cassette (maybe starting with an IRD 12-34, if I can swap the 12-13 for a 13-14), in which case I'd run a 48-34 double. (There is some irony - this is exactly the gearing I started with on my Bob Jackson when I built it in 1972, on a TA Cyclotouriste). I still have to verify the White Industries MI6 rear hub accepts an 11 speed Shimano cassette, BTW.

If I had the ability to drop the fd lower, I'd set the bike up 44-34 and use the stock IRD 12-34 cassette. I may look into what it would take to move that fd tab.

The BB I run the Sugino AT on is a Phil Wood and it's actually biased a bit out to the right as currently set up so that the 24T ring clears the chainstay. Dropping that ring off the crank would let me move the crank in slightly to get a chainline suited to a double.

So, what I envision is that I'd get the following for the conversion:
- RS685 shifters and the RS785 calipers
- RD-R8000-GS medium cage rear derailleur
- IRD 12-34 cassette, modified if possible
- 34T TA Zephyr inner ring (110 BCD)

Does this make sense?
Thanks very much!

[cmbicycles]

Maybe running an adapter that let's you drop the front derailleur would work... something like this

https://wickwerks.com/products/fit-link-adapter/