Where is the sound coming from?

[AgMar]

Nope not yet will have some time next week to go through all the suggestions raised by everyone

[AgMar]

Alright, I think I've located the source. I made a sound recording, but I can't upload it. It was the pulley wheels. I changed the pulley wheels back to the original Shimano ones and the sound has gone. I was using third party ceramic ones which have been fine for possibly 5000km or more; they still spin as well as or close to when they were new, so I still need to investigate why these pulley wheels are making the sound, but at least now the bike is silent again. Thanks to all for input and suggestions.

[kode54]

I had similar issues with the J&L pulley wheels. The bearings are crap even if they spin well...the ball bearings are tiny and has too much play in them.
I used the pulley part and replaced with steel bearings and that fixed the side-to-side play and improved shifting.

Glad you found the culprit.

[TobinHatesYou]

Alright, I think I've located the source. I made a sound recording, but I can't upload it. It was the pulley wheels. I changed the pulley wheels back to the original Shimano ones and the sound has gone. I was using third party ceramic ones which have been fine for possibly 5000km or more; they still spin as well as or close to when they were new, so I still need to investigate why these pulley wheels are making the sound, but at least now the bike is silent again. Thanks to all for input and suggestions.

Third party ceramic pulleys basically come without any meaningful lubrication, which is why they spin forever out of the box. It doesn’t take much for them to get contaminated though. And if they get contaminated they can get pitted or otherwise ruined. At this point I just use a basic NLGI 1 grease and almost a complete fill.