I recently did a big clean up of a bike that I bought and when I was washing the bike there were specs of dirt on the frame that I couldnt remove, I tried a soft brush, Muc off bike cleaner and (water obviously), but the dirt wouldnt go, but I have some motorcycle degreaser that I could spray leave and then have a got at wiping that off, but I was wondering if that would damage the paint and if so, what could I use? Thanks Charlie
You will want to look at the active ingredients of the degreaser to see if it contains any strong solvents. You will also want to consult your dealer or manual for the type of paint coating on your bike. The name degreaser is a bit of a misnomer; it contains an oil that dissolves oils within the medium which allows a majority of the dirt to slide away. However, degreasers leave a thin layer of oil no matter how much water you spray on it which is why you cannot paint over degreased surfaces.
Solvents only leave a film of solvent which eventually evaporates into the air, leaving a bare surface. However as they generally have high chemical energy, these are what can pull off finishes.
I would try low abrasive dry cleaners like baking soda or bleach powder (Comet) first as it will slightly abrade and maybe even polish your paint rather than risk dissolving it.
See Applied Science's video for details on different cleaner types application which is extremely useful in more than just cleaning vehicles.