- Tried to replace the crankset
- Replaced the bottom bracket with a new one
- replaced the pedals
- overhauled the headset
The noise only manifests when a relatively higher torque is applied and it doesn't matter if seated or standing. Moving the weight around the bike while pedaling doesn't have any significant effect on it either.
Thinking about replacing the wheels and QRs and the derailer as soon as I can get my hands on spares. I thought that the noise is so specific and strong that maybe it is a recognizable one so I can ask for a shortcut.
Update: tracked down to the wheels for now. Spare wheels make the creaking go away.