Originally Posted by
melonbar123
Briefly looking at the photos, it seems like an entry level Japanese frame. Seems like a great candidate for a single speed. The curious markings are nubs to hold clamp on shifters or shifter cable clamps in place. Lugs seem very distinct so someone might be able to identify it better than I.
+1
Well, maybe one step up from "entry level" since you have a cotterless crank with removable rings; true entry level would have a steel cottered crank or a steel chain ring swaged to a cotterless crank arm, depending on the date.
Speaking of the date, you can probably find date codes on the derailleurs and the brakes. Somewhere around 1980, I think.
The chrome steel plate at the top of the fork is a sign of a low end bike; and it's removable, of course.
I don't recognize them, but I do like the head lugs; I'd definitely do a two tone color scheme, with contrasting color on the head panel and seat tube.