I know it hasn't been discussed in this thread for a while but, any of you folks there that have a noisy cassette would you classify the noise as a ticking sound when your applying power in just those intermediate gears that are on the carbon carrier? If so I think I might have the same issue with the 9000 series cassette.
Has there been any news on this front. I know a few of you were investigating with your LBShops and distributors. Was anything learned in terms of cause and remedy?
With Ultegra 11 coming in a few months, I am thinking it may be easiest to deal with the issue for now and downgrade to some Ultegra 11 cassettes. I don't believe that Ult 11 cassettes will have the carbon cog carriers like the DA9000 does.
I work at a Trek bicycle shop and I personally have issues with this cassette as well. Talking to Trek technical support, they believe the issue to be regarding the chain angle and the machining of the cogs. The tech rep there claimed using a campy 11s cassette resulted in no ticking/derailing sound under load.
For the record, I too have issues on the big (50t) and 21, 23, 25, 28 rear cog combinations under load. I have the full 9000 set up with 9000 cables/housing on a Madone 7 frameset with 40.7cm chainstay length. I have issues with my SRM 7950 crankset and the 9000 50-34 crankset set up with Dura-Ace C35 9000 wheels.
On another note, what's up with the b-tension screw? It seems to have no use since I have that sucker backed out so far out. You would think they could cut that screw by 75% to save some weight. This is for a 11-28 cassette.