chances are if you take care of the bike it will stay like that for a long time but I am with SJX clean it up and stop the growth. you might be able to find some auto touchup to match the grey the blue may be tough to though.
OH a "new to me" bike? do we get to see more?
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“One morning you wake up, the girl is gone, the bikes are gone, all that's left behind is a pair of old tires and a tube of tubular glue, all squeezed out"
Sugar "Kane" Kowalczyk