Barrettscv 

I have a nice set of Campagnolo Chorus hubs on a bike that I'd like to install 8 speed Dura Ace shifters and derailleurs on. Looking at the Sheldon Brown cog spacing sheet, it looks like 8-speed Campagnolo cog spacing is 5mm and 8-speed Shimano is 4.8mm.

Since the derailleur jockey wheels allow for some misalignment, will this combination work?

jeirvine 

Maybe. This is worth a look, if you haven't seen it:
https://www.sheldonbrown.com/drivetrain-mixing.shtml

RobbieTunes

I've run it with tricolor 8-sp STI's, no problem, plenty of chain slop with 8-sp. However,
running DA may be another monkey.

BTW, we missed you bombing down the hills at the Dare. I only managed 42.6 mph this year, but it was a fun one.

noglider 

Probably not. The difference of 0.2mm accumulates with each shift. There are seven gaps between the eight cogs, so if things are aligned at one end, they'll be off by 1.4mm (7 * 0.2).

ThermionicScott 

If you use 9-speed (Campy) spacers instead of the 8-speed, the center-to-center spacing will go down to 4.7mm -- pretty close to the Shimano 8-speed spacing of 4.8mm. You might need an additional thin spacer at the back of the cassette to make up the difference.

And I'll let someone correct me if you can't use C9 spacers on a C8 hub.

P.S. Leaving two of the C8 spacers in place (maybe every third cog?) would bring the average spacing up to 4.8mm, but I definitely don't know how well everything would work.

Barrettscv 

I agree that the difference accumulates, however the accumulating indexing error can be reduced by setting the alignment correctly in the two center cogs. That reduces the accumulating error to about 0.7mm. My guess is that shifting into the big and small cogs will be relatively sluggish and that the operation of the drivetrain will be less than perfectly silent on those cogs.

Chrome Molly

This

Andy_K 

This is exactly what I'd try.

I've been doing a lot of experimenting with this sort of thing, using Sheldon's cribsheet as a constant reference, but I've been going in the opposite direction. I've got a bike set up right now with 10-speed Centaur shifters, a 10-speed Chorus rear derailleur, and a 10-speed Shimano cassette with 9-speed Shimano spacers on an 11-speed Shimano freehub.

I found that using the 10-speed cassette with its original spacers (leaving a 0.2mm error in spacing at each step) I couldn't get it to shift well over the whole cassette. With the 9-speed spacers (which are ~0.2mm thicker, but only four of which are replaceable) it shifts beautifully.

Going from narrower Shimano spacing to wider Campy spacing gives you an extra problem in that the limit screws don't help you with a free match on the biggest and smallest cogs. Switching to 9-speed Campy spacers would make the cassette a bit narrower than the shifting system "expects" so the limit screws would make the two end cogs line up correctly. Then, even assuming the documented spacer thickness is precisely correct (probably not true), your maximum error with be ~0.25mm on the second and seventh cogs, which is certainly within the wiggle room of a Shimano derailleur. Without changing the spacers, you'd have a maximum error of 0.7mm at the extremes. That might be OK, but I suspect you wouldn't be satisfied with it.

Barrettscv 

I'm applying the concept of combining 9-speed cassette components and 8-speed cassette components, but will try a different mix.

If I use 9-speed cogs (1.75mm) and 8 speed spacers (3.1mm) the width of the sum of these two parts is 4.85mm. This should keep the cumulative error to less than 0.2mm. I happen have an idle 9-speed Campagnolo cassette to source cogs* from.

Does this add up?

Chrome Molly

Yes, probably a better solution since you will have a hair more space before the next cog starts to pick up the chain.

repechage

My son is running Campagnolo 8 freehub and cassette with a Shimano Deore rear mech, Campagnolo front and Deore SIS thumb shifters, works pretty well, but I encourage him not to shift under heavy load.

If I could find handlebar mounts for the Campagnolo index shifters, I would go the preferred route, Full Campagnolo.

BTW, monoplaner brakes have surprising grabbing power, I considered dual pivots, but set that aside.

ThermionicScott 

Yeah, that sounds good!

SJX426 

I am interested in a variation of the above configuration, Campy 8spd Ergo Power levers with DA driveline.

I like the idea of changing out the spacers but will there be enough thread engagement with the locking ring?

Barrettscv 

What hubs? I would expect that most Shimano hubs would work, but that a spacer should be installed before the cassette goes on. Shimano makes several spacers of different thicknesses.

Dave Mayer

I have successfully run Campy 8-speed shifters and derailleurs on Shimano 8 speed cassettes. Many times. The cog spacing differences are insignificant.

If you're fussing about 0.2mm spacing, then replace a few of the 8-speed spacers with some 7-speed ones.

Barrettscv 

It's actually cheaper for me to use 9 speed cogs with 8 speed spacers, I already have a nearly new 9 speed cassette and I'll omit the 16t cog. I can find a worn 8 speed Campagnolo cassette for very little money and the spacers from it will be ideally sized.

SJX426 

Hmmm. It is a DA hub with 8speed cassette.
I may have a Campagnolo 9speed or 10 speed cassette with spacers. Thinking about slowly converting the Pinarello from DA to Campy.

Andy_K 

Do you want to run the Campy shifters with DA derailleurs and cassette or Campy shifters and derailleurs with a DA hub/cassette? The 8-speed Campy shifters + Shimano derailleurs combination isn't entirely tenable, especially if the derailleurs are 7400. However, Campy shifters and derailleurs with Shimano cassette is a combination a lot of people seem to be happy with. I think you're right that using thicker spacers would make the cassette too wide. You could use a 7-speed Shimano cassette.

Another combination that I'm using is 10-speed Campy shifters with a pre-2001 Campy rear derailleur and a 10-speed Shimano cassette. The indexing works perfectly with this combination, as well as or better than any native Shimano system I've used. Something about the Campy rear derailleur (perhaps a wider cage?) was causing it to scrape the spokes just a tiny bit under load when I used the big cog no matter how carefully I adjusted the limit screw or aligned the hanger, so I dropped the 11T cog (which I never need anyway) and installed a Gevenalle HOUP to give myself some peace of mind. If you want to go Campy without buying new wheels, I think this is an outstanding way to do it.

If you're looking for a more gradual transition, the Cyling UK mix and match tables (A guide to rear shifting | Cycling UK) say that Shimano 8-speed shifters and a pre-2001 Campy rear derailleur will index well on a 10-speed Shimano cassette (though obviously it will only hit 8 of the cogs). I'm not sure a 10-speed cassette fits on the DA hubs you have, but since you'd only be using 8 of the cogs anyway you could remove the smallest cog and put a spacer behind the cassette, similar to what I described above.

dddd

I think Andy_K made a good point about the shifting quality whenever indexing is a little off.


It is often pointed out that the pulley float and chain gap easily make up for indexing error with quiet running in perhaps every gear, but the shifting behavior becomes inconsistent, which tends to greatly reduce the bike's cable-servicing and adjustment intervals.
Under more challenging riding conditions, this can become really annoying at the same time that you need the shifting to be at it's best, which can take the fun out of friendly competition or any more-spirited riding.
It's a bit like going back to the 7s Accushift systems in the days before we had modern narrower chain to make them more forgiving to shift, often requiring annoyingly-constant fiddling to the cable adjustment.


Disclaimer: I am easily annoyed by shifting issues, though I do embrace the challenge of solving them in real time, and am always happy to friction-shift decent and well-setup components using DT levers.




.

Camilo

You should just try it. Many examples above of various iterations of Campy and Shimano 8 speed mix and match. My story is Campy 8 speed shifters and RD w/ Shimano 8 speed cassette. Worked very good. Ever so slightly clunkier than using a Campy 8 speed cassette, but well within "very good to excellent" rating.

SJX426 

@andy k @dddd @Camilo - Thank you gentlemen for the feed back. It verifies my gut tendencies. Look like the best next step would be to find a pre 2001 Campy RD.

Dimensions do not lie, however tolerances often offer exceptions. My preference is to stay at nominal. That is why I haven't "just tried it." If I am going to put time and material into the effort, it should yield a positive result. Trying to use only Campy 8 speed Ergo's on an otherwise DA 8 speed configuration does appear to have any hope of working.

My intention is to obtain either Chorus or C-Record hubs and lace up to Tubular rims for the Pinarello. Convert to Mono Planer's and install the Chorus crank in my stash.

Any recommendations for the RD?

Barrettscv 

We should talk about switching wheelsets, but I really like Campagnolo hubs and they look great on this bike.

SJX426 

@Barrettscv - I have an extra set of DA hubs. Need to check if they are freewheel or cassette. I think they are the latter. Now that I think about it, they have 7 speed cassette. I don't have a thin wall tool to remove the retention ring to pull the cassette.
I'll check at the end of my day.

Dave Mayer

Yeah, this should work. If you are within 0.2mm per cog travel 'error', you won't notice any problems, unless you have other issues such as a worn-out chain, derailleur, shift cables / housing etc.

Most of my bikes have Frankenbike drivetrains that are are mix of Shimano, Suntour, Campagnolo, Simplex, etc. They all shift brilliantly, but it is in no way by accident.

If you correctly run the math, and you have accurate measurements, and your components are in good tight condition, then the indexing will work perfectly.

I despair over garage mechanics here who blissfully extol others to slap together random components to see: "if it works...". Well, if the numbers are wrong, then it won't work, and you'll have just wasted hours in frustration. You need to run the math first.

BTW: 7 and 8 speed Dura-Ace cassette hubs... I own a few of these. They have led me down a path of misery...

Andy_K 

If you act in the next hour or so, this would work: Campagnolo Chorus 9 Speed Rear Derailleur | eBay

Honestly, my only experience is with a 1998-ish Racing T rear derailleur, which I like a lot. I'm particularly partial to the graphics on the Campy mechs of that period.

BTW, the distinguishing feature that will tell you whether or not a Campy RD has the "old" pull ratio is that the older ones have the B-screw where it attaches to the hanger (like Shimano) and the newer ones have it by the top pulley.