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Discussion Starter · #1 ·
Grrrrrr. I was never crazy about the stamped rings that came on the Centaur and lesser groups. They are less attractive and make more noise than the machined rings on the higher groups. No problem, I'll just order some rings and swap 'em out! Wrong! The stamped rings are 2.7mm vs 3.5mm for the machined rings (measured at the mounting point). Because of the way the rings mount, a thicker ring will not mount without creating a bend in the large chainring. I would rather not have to file the crank arm or the rings to fix this.

I have seen machined rings on UT Centaur groups on this site and the owners say "They came stock". This may only affect the large ring, but has anyone run into this? Know where to get rings that will fit?
 

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Are you talking about the old alloy Centuar, the old Carbon (not Ultra Torque) Centaur, or the newer Ultra Torque Centaur? I believe that there are differences between all three of these.

I have compact cranks in each of these variations - I don't know if the information I'm providing applies to 135bcd (53/39) cranks.

The old alloy Centaur stuff (and lower groups) I believe was a "standard" 110 bcd - not compatible with Record machined rings, but I believe, compatible with a lot of aftermarket stuff. Correct me if i'm wrong - I don't know for sure, and haven't tried to replace my rings with non campy stuff, but I do know that the bolt pattern is NOT the same as 110 bcd Record.

The old Carbon stuff shared the Campy specific 110 bcd, with the single rounded point that bolted into the back of the crank arm. Machined Record Rings ARE compatible with these old centaur carbon cranks. I've replaced a pair myself, with no problem. My understanding is that these older crank arms are identical to the record arms, with the differences being the bottom bracket width they were designed for, and the lower quality rings. You can still find these old record rings on the various UK sites, etc.

I haven't tried to move rings around on the new UT stuff. Looking at it, i'm very surprised that they aren't compatible with the record rings - they appear to share the Proprietary bolt pattern that used to be reserved for Record.

Hope some of that is helpful...
 

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i have the machined rings on my centaur alloy UT... the latest ones were downgraded.

Look into TA specialties and Stronglight, campy rings ain't what they used to be anyway. snapped a tooth clean off my (machined) centaur ring.

I don't know exactly what you mean tho, cos i currently have my veloce UT (which always had the cheap stamped rings) with 05 record rings on it now no problem. did the swap meself.
 

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Machined rings are nice but not worth the extra money. I'm using Daytona 10 sp now. It works just as well as the Chorus it replaced. If you must have machined rings old square taper Record/Chorus cranks are still available on ebay cheap. They're under a $100 and that's cheaper than the cost of rings. Good luck
 

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Discussion Starter · #7 ·
I suspect the aftermarket are all matching the 3.5mm spec. I noticed that Campy took the large rings off their site (as replacements) suggesting something is up. I had the old Chorus on my last bike, but I think I will stick with the new UT... they are much stiffer (as determined by FD rub). I think the new rings only are an issue from 2009 on. I have seen several sets of UT Centaur with machined rings, pre 2009.
 

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I ran into the same problem with my centaur cranks,so I was debating filing down the flat bolt hole area behind the crankarm about 0.8mm or doing the same to a record outer chainring i had planned on using. What did you end up doing?

The new stamped centaur chainrings look like they belong on a department store bike.
 

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For those who have reasons to replace the outer chainrings for the Centaur, Veloce and Mirage UT cranksets (135 and 110BCD), TA Specialites have compatible replacements but they are quite pricey. The 5th arm is slightly offset and machined thinner to fit.

Check out the link here: http://www.chickencycles.co.uk/index.php?cat=32&ord=2

ICYCLES Ebay store also has the machined Centaur 53/39 chainrings going for $50 a pair. Not a bad deal so better grab it before they run out.

http://cgi.ebay.com/CAMPY-CENTAUR-1...Cycling_Parts_Accessories?hash=item35a474660b
 

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Discussion Starter · #12 ·
"The Tivano is compatible with Campagnolo Centuar carbon/Veloce/mirage Ultra-Torque cranks. Machined with great precision using CNC. The 5th arm is machined thinner for perfect compatibility, the bolt hole has no recess for bolt head as this bolts straight into back of the crank."

Note that the ones you show on eBay are NOT the same. They are specific to older Centaur with the machined rings. If you have machined rings, you can use most machined 10spd rings .... if you have stamped rings, then the TA Tivano are the only ones I have seen that can replace the Campy stamped rings now on the lower-end Campy cranks.
 

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waterford853 said:
Grrrrrr. I was never crazy about the stamped rings that came on the Centaur and lesser groups. They are less attractive and make more noise than the machined rings on the higher groups. No problem, I'll just order some rings and swap 'em out! Wrong! The stamped rings are 2.7mm vs 3.5mm for the machined rings (measured at the mounting point). Because of the way the rings mount, a thicker ring will not mount without creating a bend in the large chainring. I would rather not have to file the crank arm or the rings to fix this.

I have seen machined rings on UT Centaur groups on this site and the owners say "They came stock". This may only affect the large ring, but has anyone run into this? Know where to get rings that will fit?
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I ran into the same problem with my centaur cranks,so I was debating filing down the flat bolt hole area behind the crankarm about 0.8mm or doing the same to a record outer chainring i had planned on using. What did you end up doing?
The new stamped centaur chainrings look like they belong on a department store bike.
A buddy of mine just encountered the same issue on his 2009 Centaur carbon cranks. He hated the original cheap Centaur chainrings when it arrived and after using the cranks for a couple of weeks. At that point he acquired some new 2009 SR 11SP chaininrings 53-39 to mount and he was real happy until the same mounting issue problem popped up. I am thinking he could just carefully file the 0.8mm off the carbon mounting surface and the newer chainrings would mount Aokay. Its a very small dimension to remove (but obviously significant in this case) and a small flat file and some careful work should solve it.

(and i did beat him up over the facts that if he had either returned the crankset right away or purchased the Chorus 11SP cranks in the first place as he had planned it would have avoided all of this plus he has now not saved anything after purchasing the new chainrings... anyway, moving along...)

Comments/thoughts on doing the above as a solution? Thanks in advance.
 

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???

If the rings don't fit the crank, filing on them may not be wise. The important thing to maintain is the correct chainring spacing of 7.7mm tooth to tooth and the chainrings must also run true. You should figure out the consequences of modifing the rings before doing it. A file is poor tool to use for accurately removing that much material.
 

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C-40 said:
If the rings don't fit the crank, filing on them may not be wise. The important thing to maintain is the correct chainring spacing of 7.7mm tooth to tooth and the chainrings must also run true. You should figure out the consequences of modifing the rings before doing it. A file is poor tool to use for accurately removing that much material.
No, no no... not suggesting filing the chainrings themselves! that would be crazy... the filing is needed to remove material on the one mounting surface of the crankarm (the hidden chainring mount point behind the crankarm).
 

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Discussion Starter · #16 ·
To c-40's point, keep in mind where that spec may be coming from. Note that the spider arms fit to the outside of the ring and the arm of the crank attaches to the inside of the ring. If you just file the arm, the spacing of the rings may be off causing poor indexing. Sell everything on eBay and start over. The alternative could be a useless crank and a lot of frustration.
 

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still...

campagnoloneutron said:
No, no no... not suggesting filing the chainrings themselves! that would be crazy... the filing is needed to remove material on the one mounting surface of the crankarm (the hidden chainring mount point behind the crankarm).
Still highly inaccurate and you need to be sure of the results before doing it. This advice is from a long time machinist.
 

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I'm glad I saw this thread. I was just about to pick up a cheap 2006 centaur crank as a ring donor for my new alloy UT cranks (the new rings really are quite nasty looking). I wish Campy had just used a spacer between the ring and the arm if they had to make the rings thinner-they could have kept the arms cross compatible that way. Really frustrating.

I suppose all component manufacturers are doing the same thing, but that doesn't mean I have to like it.
 

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I have a set of 2008 Centaur ring with only about 100 miles on them. I pulled them to put a single carbon fiber tt ring for my tt rig. Will let them go cheaply. If interested PM me.
 

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I'm thinking of filling my crank arm also, but would take it to a machine shop if i could find one that will charge a reasonable price. Anyone know of a good machine shop that could do this in the sacramento/nor cal area?

I've been using campy for over 20 years, have used & interchanged multiple groups, and this is the first time i have felt shimano'd by them.
 
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