Heh. Just kidding. Here's the badge:
As far as I know, this is a rare one for Sekine, I'm thinking of cleaning it up and re-doing the paint so it looks nicer.
Gotta love how faded the original colouring is on that head-tube.
BTW, I think T-Mar told me a few years back that this is a 1980 Sekine RM-40.