On my wife's new bike, I swapped the stock cassette out to a SRAM PG-970 11-34 to help her out on our vertical rides. I installed the brand new PG-970, along with a brand new SRAM PC-991 chain to accomodate the larger cassette. All of a sudden the buttery smooth drivetrain turned to junk, with clunks so hard I could feel them in the pedals, mostly in the 4th smallest cog. To eliminate all other possibilities, I took the 2 month old SRAM PG-970 off my MTB and put it on my wife's bike. Problem disappeared. Then I put the suspect cassette on my bike, and had the exact same problem. Analysis with digital calipers revealed that the 4th cog (15T) was canted on the body by 1.2 mm, which was not visible to the naked eye.

I called Jenson USA, where I bought the new cassette, and they overnighted me a replacement (kudos to JensonUSA). Same problem. Went through the motions, and installed the new replacement cassette on my MTB, same problem again. Just to triple check, I put the cassette from my bike on my wife's, and it was perfect. I also took my complete wheel with my cassette, installed on my wife's bike, no problems, and my wife's complete wheel on my bike, same problem.

Bottom line, the 2 brand new SRAM cassettes were junk. I'll be calling Jenson again tomorrow, sending the SRAM garbage back, and ordering a Shimano cassette. I will never buy another SRAM cassette, which is unfortunate, because I have always liked them in the past. I know daredevil had the same problem because I discussed it with him, anyone else?