I recently picked up a couple of old 12-speed road bikes that were going to be scrapped. One of them has no decals on it. The brand doesn't appear to be stamped on it anywhere either. Based on some of the components and characteristics, I'd guess that it's mid to late 80s. It does have a serial number (W 71385) but I couldn't figure out which bikes used that type serial number.

Does anyone know what brand used serial numbers like that?

(I can't post photos yet.)