I've just picked up an old alloy Koga Miyata Super winner which I was hoping was a steel one badly listed that I would keep, but it wasn't.....anyway, it has several Koga branded bits on and a sante groupset (less the rear mech which is 600 tricolour), but the interesting thing is the saddle......it is a selle rolls but the little brass badge on the side says Koga Miyata instead of rolls.....is this common?