Impossible Rattles

[CharlieB]

Not looking for help - just seeing if this strikes a chord…

Why do bikes rattle from a particular location for a period, when after a thorough check, there is nothing discernably loose to rattle?

Why does the rattle then stop the following day/commute?

 

[Fnaar]

I usually find it's my knees.

 

[swee'pea99]

They like to tease...

 

[Hacienda71]

My bike was rattling a lot on my Sunday AM ride it got so concerning I pulled up got off and checked everything I could think of. Nothing loose. Took a swig of my drink from my bottle which I had chucked some ice in before leaving and realised the rattle was the ice cubes.