I just replaced the jockey wheels on my 6800 ultegra rear derailleur. I noticed some clicking on a couple of the cogs on the the cassette. Upon further investigation, I discovered it was the new guide pulley wheel that was getting stuck and sucking up the chain for a moment before it released which created the click. I purchased the correct replacement jockey wheels on amazon and they look legit (I purchased a fake shimano chain on amazon in the past, so I'm skeptical of authenticity). The chain has maybe 200 miles on it.
My question is, has anyone else experienced this issue with new jockey wheels? My thinking is that after a couple rides the wheel will break it and and round off ever so slightly as to not have the crisp new edges which are catching the chain slightly. It's only happening on two of the cassette cogs and only on, I believe, one of the jockey wheel teeth. Other than waiting for it to break in, I could file down the tooth slightly.. This doesn't seem right..
Let me know what you think and what your experience has been in the past which replacing jockey wheels. If it is a fake shimano part, I was thinking the best way would be to compare the bearing manufacturer. The marking on the bearing is -NMB R-1760D THAILAND-. Does this sound like a legit bearing shimano would use? I will link a video showing the issue. If you look carefully, the chain is sticking to new guide pulley, but only happens when in the 2nd and 3rd largest cassette cogs.