Potenza shifters with new Centaur 11 rear mech?

Discuss light weight issues concerning road bikes & parts.
morrisond
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by morrisond

Both Potenza and Centaur 11 are Powershift - and from the article below use the same internals.

This is from Bicycling.com

"The main difference between Power Shift and Ultra Shift is the former does not have the ability to do multiple rear-derailleur upshifts (higher/harder) in a single press; instead, they must be fired off one by one. This difference explains Centaur’s (and Potenza’s) dropped, downward angled shifter button on the inside of the ErgoPower bodies (in Ergo Power, the lever is flat-topped, and sits higher).

The Power Shift internals in Centaur use different, and more durable, material than what was found in Potenza. However, Riddle indicated that a running change will see this new material incorporated into the Potenza internals as well."

I quite like the Powershift buttons vs SR. I have Potenza HO on my gravel/winter bike and the levers feel like the SR EPS on my Road Bike.

Very positive shifting on Potenza HO. Front works great as well.

by Weenie


robertbb
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by robertbb

Bloody running changes. How is one supposed to know what they're getting when they buy?
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bm0p700f
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by bm0p700f

I am not confused. Centaur 11 speed has a different cable pull to potenza for the RD.

The centaur RD does not have this change for fun. As it a lower tier RD to cut costs for the grouspet it has been made with a limted range of cassettes in mind 11-29T to 12-32T. Cassettes out that range wont get precise shifting. the more your deviate the worse it would get. What is lacking is the mechanism present in the higer tier groupsets that allows the jockey wheel to track the cassette over a wider range of sprockets size. So proper tracking is acheived through the geometry of the RD instead necessitaing the cable pull change.

you would get decent shifting with a 12-27T cassette but maybe not perfect. however try a 16-27T and the shifting would be slow going up or down and it would never be spot on except in one part of the cassette where the jockey sits at the right distance from the cogs.

An example of this try a 11-21T cassette on a record 11 speed RD. Miche cassettes in 12-27T shift perfectly with Record or SR mechanisms but not the 11-21t because top jockey cant track the cassette properly and the shifting into the smaller cogs is slower than ideal.


Campagnolo think the centaur is aimed at the sportive market and the customers for it will only want a 52/36T at the most and 11-29T as the smallest range cassette such is the modern way. So campagnolo figured if this is the modern way then they can make these design changes without cauing a problem. If you are buying potenza you are buying a more sophisicated system which is why it cost more. same with chorus. you cant mix and match potenza RD's and chorus RD's either as spring in the RD for power shift groups is weaker than for ultra shift groups creating drift issues with the shifting.

So just because you read both potenza and centaur use powershift ergo's you can then assuming.....

I am just savin Greame wirting all this.
Last edited by bm0p700f on Thu Feb 22, 2018 7:49 am, edited 1 time in total.

robertbb
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by robertbb

[Double post deleted]
Last edited by robertbb on Thu Feb 22, 2018 5:59 am, edited 1 time in total.
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robertbb
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by robertbb

bm0p700f wrote:
Thu Feb 22, 2018 12:14 am
you cant mix and match potenza RD's and chorus RD's either as spring in the RD for power shift groups is weaker than for ultra shift groups creating drift issues with the shifting.
Kinda. I'm runnning two Potenza RD's on two full Chorus 2017 groups. Shifting is about 95% perfect. Veeeeery occasionally it will hesitate, just slightly, shifting into smallest 2 cogs (symptom of the less powerful spring) but otherwise it's been a cost effective way of getting a medium cage derailleur that will support the 32t cog I use in alpine areas.

What exactly are drift issues, by the way?
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bm0p700f
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by bm0p700f

as I said the spring in the RD is different and weaker in the potenza as it does not have to pull back the overshift that ultrashift makes which is why ultrashift is slicker and powershift more clunky for the lack of a better term. so using a potenza RDwith chorus shifters you will be fine to start with but add time and cable wear/weather the down shift or the upshift will start to play up like you are seeing. Campag like everything to be perfect you are accepting compromise.

robertbb
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by robertbb

bm0p700f wrote:
Thu Feb 22, 2018 7:53 am
as I said the spring in the RD is different and weaker in the potenza as it does not have to pull back the overshift that ultrashift makes which is why ultrashift is slicker and powershift more clunky for the lack of a better term. so using a potenza RDwith chorus shifters you will be fine to start with but add time and cable wear/weather the down shift or the upshift will start to play up like you are seeing. Campag like everything to be perfect you are accepting compromise.
This is gonna cost me $, lol.

I can get some "older" (i.e. non HO) chorus derailleurs at a good price. Will I be able to attach the Potenza medium-length cages easily enough?
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freehub
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by freehub

bm0p700f,
I have a couple of earlier Ultrashift bikes with Powershift rear derailleurs and you are quite right the internal friction of Ultrashift levers causes less than perfect shifting down the cassette with Powershifter RD's with lighter springs. Mismatched front derailleurs poses no compatibility issues of note I can detect. Good shifting in the front with US lever and PS level front derailleur.

Is there any way to retrofit stouter springs into Powershift rear derailleurs? You know if Graeme or anybody can do this?...believe RD bodies with springs can't be disassembled...are riveted and non serviceable I believe...by factory intent of course. :wink:
Perhaps retrofit Ultrashift RD bodies onto PS deraileurs?...or not worth it.

You seem very knowledgable and I would like A level shift performance and would say my rear derailleur setups are B level...down the cassette in back only of course...not helped also by cable routing through the handlebar which introduces a hint of cable drag as well.

Thank you.

robertbb
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by robertbb

While we're asking these types of questions, I have another to add: the medium cage Ultra Shift derailleur says "29-32t only". Does this mean it absolutely will not work with a 25t, under any circumstances? (understand I may need to use a different length chains..)

I always run a 12-29 out on the road, but I'd like to be able to run a 12-25 for indoor training sessions so I can control cadence/power with more precision.

(I run 50/34 chainrings, btw).
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bm0p700f
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by bm0p700f

The spring in the derailleurs look fixed to me i dont think there is any way they can upgraded.

Medium cage rd can be used with smaller cassettes but the only issue would be if the top jockey wheel sits any further from the sprockets Changing the cage should not do that but longer cages do flex a bit more leading to less precise shifting. I have a record 10 speed rd medium cage with a 12-25T and no issues. Still you got a med cage for big cassettes so I would stick to that and if short gearing is not needed go 1x with garbaruk chainring.

That said depending on the mech hanger shape the short cage rd might cope with bigger cogs than its meant to. My record 10 speed medium cage can tolerate a 12-32T cassette with 53-39t rings with chain tension in all gears. Apparantly the long cage 10 RD's can work up to a 40T

nachetetm
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by nachetetm

morrisond wrote:
Tue Feb 20, 2018 6:11 pm
Both Potenza and Centaur 11 are Powershift - and from the article below use the same internals.

This is from Bicycling.com

The Power Shift internals in Centaur use different, and more durable, material than what was found in Potenza. However, Riddle indicated that a running change will see this new material incorporated into the Potenza internals as well."
Does this changes with Potenza internals has to do with the vagueness associated with the levers to go into bigger sprockets? Many reviewers mention it and it is actually the biggest downside for Potenza in my opinion. After using it for a year I'm very happy with the groupset (and I much prefer it over Ultegra) but if I could improve the feeling of the levers I would be so much happier. In my opinion is the only downside.

JoO
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by JoO

bm0p700f wrote:
Fri Feb 23, 2018 12:02 pm
The spring in the derailleurs look fixed to me i dont think there is any way they can upgraded.
you could try to put a 1 mm washer beween the hanger and derailleur.
That would 'load' the spring a bit.

Might not help a lot but it is worth a try.

JoO
Posts: 48
Joined: Thu May 04, 2017 7:30 am

by JoO

bm0p700f wrote:
Thu Feb 22, 2018 12:14 am

The centaur RD does not have this change for fun. As it a lower tier RD to cut costs for the grouspet it has been made with a limted range of cassettes in mind 11-29T to 12-32T. Cassettes out that range wont get precise shifting. the more your deviate the worse it would get. What is lacking is the mechanism present in the higer tier groupsets that allows the jockey wheel to track the cassette over a wider range of sprockets size. So proper tracking is acheived through the geometry of the RD instead necessitaing the cable pull change.

you would get decent shifting with a 12-27T cassette but maybe not perfect. however try a 16-27T and the shifting would be slow going up or down and it would never be spot on except in one part of the cassette where the jockey sits at the right distance from the cogs.
This is not different than older style campagnolo derailleurs is it?
The new "embrace" design allows the newer derailleur to have the top jockey wheel closer to cogs (and more chainlinks engaged).

My guess would be that centaur is similar in action than old campagnolo 'non-embrace' derailleurs.

freehub
Posts: 45
Joined: Sat Feb 17, 2018 2:23 pm

by freehub

JoO wrote:
Sat Feb 24, 2018 5:04 pm
bm0p700f wrote:
Fri Feb 23, 2018 12:02 pm
The spring in the derailleurs look fixed to me i dont think there is any way they can upgraded.
you could try to put a 1 mm washer beween the hanger and derailleur.
That would 'load' the spring a bit.

Might not help a lot but it is worth a try.
I am not sure that a 1mm displacement would improve response of running Ultrashift shifters with weaker spring Powershift rear derailleurs...what I run. Reason is...spring rate is less about displacement than it is the potential energy of the spring based upon wire stiffness, number of coils, wire diameter of the spring itself.

But will ask, is your posited suggestion something you have done with success if running Ultrashift levers with PS rear derailleurs?
Just doesn't seem viable to me it would help even fractionally to wind the spring a hint more.
Thank you.

by Weenie


AJS914
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by AJS914

For a while it may have been necessary to mix Chorus/Record levers with a Potenza rear derailleur or the medium cage, but now you can get a Chorus HO Medium rear derailleur for under $200. Why bother trying to mix and match now?

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