[curlybro]

I ran SRAM 9 speed on my Campy Record 9 speed group and it shifted and felt great. I read a lot about chain spacing before I bought it though. I found this article below where they talk about the chain spacing of 10 and 11 speed generations.

Originally Posted by http://cyclingtips.com.au/2014/10/mixing-groupsets-what-works-together-and-what-doesnt/

CHAINS AND CASSETTES

According to Leonard Zinn testing, all 11-speed transmissions are compatible. A comparison of a Campagnolo 11-speed cassette with a Shimano equivalent demonstrates that the cog spacing is well matched. However, there is a measurable difference in the width of each company龍 11-speed chain (Shimano龍 chain is 5.62mm wide, Campy龍 is 5.50mm).

In practice, the measurable differences account for little and a Shimano 11-speed cassette works well with a Campagnolo groupset, and vice versa. Neither combination is perfect though. The imperfections express themselves in the form of a little extra chain noise and/or occasional lazy upshifts for some, but not all, of the rear cogs. Overall, the compatibility is more than adequate in most circumstances, though not all users (or fussy mechanics) will be satisfied.

For 10-speed users, there is also reasonable compatibility between Shimano/SRAM and Campagnolo. While the chains are almost identical in width (Shimano龍 chain is 5.88mm versus Campy龍 5.90mm), Campagnolo employs variable spacing that leads to some extra chain noise and lazy upshifts that is more obvious than that seen for 11-speed transmissions. Regardless, the compatibility is more than adequate in an emergency, but the mix is unlikely to satisfy all users.

Attempting to mix 10- and 11-speed cassettes will cause significant problems due to differences in cog spacing and/or the width of the cassette. For Shimano/SRAM, 11-speed cassettes are too wide to fit properly onto 10-speed freehubs, and 11-speed chains are a little narrower (5.62mm versus 5.88mm). In contrast, Campy龍 10- and 11-speed cassettes will fit onto the same freehub body, but the 11-speed chain is significantly narrower than the 10-speed chain (5.5mm versus 5.9mm).