Any ideas for keeping older rubber bumpers "in shape"? I just received a Viking upright, quite good shape, but the bumper is starting to crack (dry out?) on the corners.
I use Vinylex on my rubber; it's like ArmorAll, but does a better job of restoring softness and colour. Expensive, but a little goes a long way. Every auto parts store of decent pretensions carries it; it's made by the same company that makes Lexol for leather.
Sometimes on slightly degraded rubber, a light sanding with fine sandpaper (300 grit or so) will take off the funky surface. I never sand much; it's easy to lose the contour of the rubber. This trick does not work on ribbed or patterned surfaces, of course.