Please help me identify my '80's Bridgestone bicycle

[Lazerman]

I attached a picture of the bike I recently purchased, and I believe I found the serial # under the bottom bracket of: "L211234"

From what I've read on another post, S/N's beginning with a letter means the frame was built in their "Sport" factory (in Japan) .

This bike has been transformed into a single speed, and I love riding it (VERY lightweight). But I know it was not always a single speed, very apparent.

I can add more pictures or answer any questions.

ANY HELP GREATLY APPRECIATED!

Thanks!