Originally Posted by
sreten
Hi,
Because I don't wash off the small amount of WD40 residue.
It helps with dirt not sticking the frame, and what is left e.g.
on the front derailleur and the cables does its original job,
i.e. stopping things going rusty.
rgds, sreten.
Think about it. If you have a frame without oil and grease on it, the dirt has less to stick to. Spray oil on something and you provide a vehicle for the dirt to stick to.