Olivia Neutron-Bomb, the aptly nicknamed John Revolting, Flashdance....it's amazing how one little 6-letter word can conjure up all those images out of a question about quietening down a noisy geared motor.
Many years ago when I worked on some real, heavy engineering projects, I discovered that there's some fantastic science behind modern oils and grease. Semi-synthetic materials provided bespoke lubrication in many applications, extending service life and reducing maintenance. In more recent times, we have seen moves towards fully synthetic oils, indeed many cars nowadays run on those modern oils from new.
As for the application required by the OP, I agree with others that Castrol LM is probably about as good as it gets for an off-the-shelf product. It will provide optimum lubrication without creating additional drag. As for sound-deadening, my advice would be to use a direct-drive, hub-motor bike instead!
Panasonic crank-drives are almost silent too but I digress.......
Movies are far more interesting than the properties of lubricants and although I have never been a big fan of Bond films, I went to see Skyfall last night and came away thinking it was the best Bond film ever! Sam Mendez, the director, has remained faithful to the style of the previous films so the model is pretty much what one might expect. He has managed to modernise here and there and has also introduced one or two new characters who, I'm certain. will feature in future Bond films. It's a really well done action movie, true to the genre for the most part and, I think, very watchable.
Can't wait for the next one!
Indalo