Recently, my seatpost -- or maybe it's the saddle -- started squeaking whenever I hit a bump, or whenever my cadence is over about 105 rpm.

I *thought* it might be my carbon seatpost, because a while back my wife's bike exhibited the same symptoms (making the same sound) and through trial & error I corrected hers simply by removing & cleaning her seatpost, then reinstalling & tightening it.

I tried that on my bike & it didn't help.

I'm going to try a different saddle (if the snow ever lets up) to try to confirm or refute that item as the cause, but meanwhile just wondering if this is a commonly occurring situation? Any ideas?

My saddle is a Fi'zi:k Aliante Sport Mg, seatpost is Cannondale Fire carbon (I suspect this is an OEM'd FSA SL-K), frame is Cannondale Synapse carbon. Bike only has about 3500 miles on it.

Thanks.

Rails where they attach to the post clamps? Sheldon Brown has a squeak area on his site - might address it.

I had a squeak that I narrowed down to the saddle rails (Selle Italia titanium rails on an aluminum Campy seatpost). I put a little grease on the rails and retightened.

I say it may be the seat post where it tightens to the rails may have become just so slightly lose as to create a squeak.