I now have hundreds to thousands of high resolution photos of RR graffiti taken all over US and Canada. As a rough guess I would say that 90% of the stuff you see on the cars is unartistic junk or even plane out vandalism.
Most RR graffiti is tagging of some sort. Like a signature practiced over and over again slowly begins to distinguish itself, tagging is visual nom de plume. They are mostly text based and largely resolved from a narrow repertoire of post modern “Kaiser zeit Gotisch” fonts all tangled up in competing and suggestively (but rarely successfully) ambiguous layers. Like a good signature, a graffiti work will vary with each iteration. I have seem the work below done with mods on at least one other car..
Here is a ten percenter..
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Hi this is tooo cool