Originally Posted by Grasschopper
Well a bit of research shows that the SRAM 1070, and 1090 chains are 5.9mm wide while the Shimano chains are 6.1mm wide. I wonder if those .2mm are getting you? Campy Ultranarrow chains are also 5.9mm
I called SRAM and they said it should be completely cross compatible, but what you are saying could be the difference. They also said to make sure that all of the smaller cogs are not on backwards. I am pretty sure they are all on right, but I told him I would check when I get home. He also said to make sure the chain was lubed and if all of this was done to take it to the LBS where I got the cassette and have them check it out and call them.