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I just replaced my front cogs and back sprockets with new ones (I didn't use a torque tool or replace the chain). I also replaced the sealed bearing bottom bracket on my pedals. The old bearings were 115 mm long and the new one is 117,5 mm long.
Now I feel some sort of vibration, and there is a noise like the gear wants to change, but the rear derailleur is set correctly with one click per gear. What can cause vibration and noise from the chain?
If you changed the crank length then the front derailer likely needs to be adjusted, and the rear may need a few tweaks. Also, when you change the rear cluster there can be a difference of a mm or two between old cluster and new, requiring adjustment of the rear derailer.
Have you readjusted both derailers "by the book"?
(Whether or not you used a torque wrench would have little bearing on this issue, though you need to be sure to check that your crank bolts are tight every 200km or so for the next 1000km.)
Was the reason for the gear change because they were worn? If they were worn the chain most likely is also worn unless it was changed recently. The general rule with chains is to replace it when the cassette is changed. As the chain wears it gets longer and won't match your cassette. Your old chain wore as the old cassette wore so they matched. Slide the chain off the crank and spin it by hand just to verify that it spins easily, this will rule out a bad bearing (sometimes new isn't perfect).
a. sorry for my limited English cycling jargon
b. by absence of a chain tool, I too replaced my cogs but not the chain. And was surprised by the rattling sound.
c. Everyone tells me to replace both at the same time. That got me thinking: why?
The chain will wear (cfr. wikipedia). The links will slack. As a result, with new sprockets, the shackles will be 'squeezed' together to match the sprocket teeth. Once a link leaves the sprocket, it will be allowed to stretch away to it's full length.
This will cause a rattling of the same frequency as when it 'tries to shift gears'.
