I am having problems understanding the source of a noise.
I would describe the noise as a intermittent crack or click that seems to come from where the seatpost encounters the frame. It stops when I stand on the pedals, and it seems the cracks arrive when I pedal some more vigorously, or when the wheels roll over some discontinuity of the road.
When I am off the saddle, the noise seems to be reproducible if I grab the saddle with one hand, the handlebar with the other hand, then I pull the saddle backwards.
Needless to say, this noise is unnerving, especially because I am not sure I am ruining the structural integrity of the bike.
Different things I tried, after reading here and elsewhere:
- remove the seatpost, clean it and reinstall it after putting on a little bit of grease on the seatpost
- remove the seatpost, clean it and the frame, put some grease inside the frame (just a bit), and reinstall the seatpost
- remove the saddle, clean all parts that connect the saddle to the seatpost, reassemble
- I bought a dynamometric wrench to be sure to torque the seatpost clamp according to specs; a couple of times before that, though, I screwed the clamp by hand: not sure I screwed it in too tight or not tight enough
- also tried greasing the saddle rails. Apparently no gain. Pretty sure at this point the noise does not come from around the saddle, but where the seatpost encounters the frame
- tried swapping saddles, no gain. Greased again the frame, this time more generously, and it seems to perform better. Still some clicks after ~25 km, so I will try again with a more specific product (I've been using a generic grease)
All these measures seemed to help a little bit, but after some kilometers in the noise starts again. I didn't try yet to install a different saddle, but I doubt it would be a solution because as I said the noise seems to come from elsewhere.
In case they are relevant, here some details about the components:
- Saddle, Brooks C17
- Cannondale Topstone Alu frame
- stock seatpost (I believe it's a Cannondale C3, 6061 Alloy)
Thank you in advance for any advice you can provide