10 speed DuraAce with Campy cogs

[Ken Robb]

On the new/old Legend I find that the cassette that works fine is Campy 11-23 on Ksyriums SL wheel. The teeth on the wheel are the irregular Campy spacing. A bit of a surprise. I need help with hills beyond 39/23 so I wonder: Can I swap some cogs and maybe even use a 29 with DuraAce 10 spd rear derailer? I wonder if this already has some custom spacers or if the stock Campy cassettes just work?

[dbrk]

I think I didn't understand exactly what you said but that I know what you want to know, that is, can you use a Campag 10spd cassette with a DA10 rear der. Answer: yes. Will it shift to the 29? Yes. No need for spacers, no real monkey business, just an ordinary derailleur adjustment, a competent mechanic will get this to zoom without a nick.

dbrk

[Ken Robb]

thanks for that info. While googling the question I found a quote from a tech with Shimano saying that we could put Campy cassettes in a 10 speed Shimano drive train and be happy just by adjusting the limit screws. I will be really happy if I can use a 29 cog. I think Shimano says the rear derailer is good for 27 teeth and Grant P.says the 9 spd ones easily handle 28 teeth. 29 wouldbe a big help.

[coylifut]

I've seen people run 32 cogs on DA derailleurs at a particularly hilly cross race this year. I was both shocked and covetous at the same time. I’ve run Campy 10 wheels on my DA 10 bike as well. Works fine

[Dave]

Shimano spacing is 3.95mm and Campy is 4.12mm, the diffrence is over 4% per shift and the error accumulates on each shift. If you use a campy cassette on a shimano drivetrain, it will undershift every time. If you carefully center the derailleur in the middle of he cassette the derailleur positioning erro still accumulates to 19% at the extreme ends. There would be no need to change the limit screw position on a shimano drivetrain, because the derailleur will never shift far enough to either side.

If you do the opposite and use a shimano cassette on a campy drivetrain, the derailleur will overshift every time and turning the limit screws in would be required to prevent overtraveling at the extreme ends.

All that said, campy offers a 12-25 which would help on the hills and shimano offers a 12-27. Why would you want to make a huge leap from an 11-23 to a something as low as a 29?

Neither brand allows "swapping cogs" since most are permanently riveted in pairs on carriers. The lowest level Centaur and Veloce cassettes have mostly loose cogs, except the last two. If you take cogs out of their proper sequence, they will no longer have proper radial "timing", which will affect the shifting, and/or you'll create an overly large jump between cogs somewhere.

If your Ksyrium wheels have the new FTS-L hub, then the smart thing to do is change out the cassette body ($50) and use a Shimano 10 cassette.

[davep]

You can also get a Shimano 12/30 from Sheldon Brown - Harris Cyclery. I have one that works fine with a standard Ultegra rear d, so I would think a Dura-Ace will work also.

[flydhest]

Dave,

This is a new bike to Ken and he said he wants a lower gear than a 23. A 13-29 cassette is great for people who need a lower end and so few people really need a 53-12 or 53-11 that the sacrifice at the top end is negligible.

Moreover, measurements and such are all well and good, but if a combo works, it works. It doesn't matter if the spacing is 4% different or not.

That said, and I don't know the details, davep's suggestion about a Shimano 12-30 sounds like the best of all worlds.

[coylifut]

Shimano spacing is 3.95mm and Campy is 4.12mm, the diffrence is over 4% per shift and the error accumulates on each shift. If you use a campy cassette on a shimano drivetrain, it will undershift every time. If you carefully center the derailleur in the middle of he cassette the derailleur positioning erro still accumulates to 19% at the extreme ends. There would be no need to change the limit screw position on a shimano drivetrain, because the derailleur will never shift far enough to either side.

If you do the opposite and use a shimano cassette on a campy drivetrain, the derailleur will overshift every time and turning the limit screws in would be required to prevent overtraveling at the extreme ends.

All that said, campy offers a 12-25 which would help on the hills and shimano offers a 12-27. Why would you want to make a huge leap from an 11-23 to a something as low as a 29?

Neither brand allows "swapping cogs" since most are permanently riveted in pairs on carriers. The lowest level Centaur and Veloce cassettes have mostly loose cogs, except the last two. If you take cogs out of their proper sequence, they will no longer have proper radial "timing", which will affect the shifting, and/or you'll create an overly large jump between cogs somewhere.

If your Ksyrium wheels have the new FTS-L hub, then the smart thing to do is change out the cassette body ($50) and use a Shimano 10 cassette.


I understand the math here , but it has worked in the field the two times I've needed it. When I first received my DA 10 bike, I damaged a wheel and borrowed a friends Campy 10 wheel and rode it for over a week. I didn't have to adjust the mech at all. No limit adjustments, no barrel adjustments. It worked flawlessly. The second time, I took a wheel from the wheel car. When I gave it back, I was surprised to find it was a Campy 10 wheel. So, it'll work. Is it ideal? Clearly no. The custom cassette option does appear to be the best course of action.