Great find. Yeah, they ride great. The RB-1 was probably the best bargain in road machines at the time. Well-designed, fun to ride, well-thought out parts specs - just a lot of bike for the buck.

From that paint job and those graphics, it is a 1992 model. (I had a 1992, but in red.) I believe that RB-1's went to all-yellow the next year.

FYI, moustache bars were not standard on the RB-1, certainly not in 1992; drop bars were. Moustache bars came on the XO-1 and a variation of those bars were on other XO models, but not anywhere else. Also, DA was not standard on 1992 RB-1's. The cranks, hubs and derailleurs were 600's (equivalent of Ultegra now) and the brakes were some sort of Dia-Compe or Gran-Compe sidepulls. It also ran a seven speed drivetrain, not an eight, and Shimano barcons were standard equipment. (The 1993 yellow RB-1s had 8-speeds with brifters, the red ones stayed with 7-speed and barcons. IN 1994, both came with 8 speed brifters.)

The stem in your photo looks like the original Ritchie, but the seat post is after-market, because the RB-1 came standard with a no-name post that was not that long. The original saddle was some sort of Avocet, I think - all I know is that I swapped mine out ASAP.

Oh, and the tubing was Ishiwata.

I loved my RB-1. I'd still be riding it except it developed a nasty crack in the BB area that involved the downtube, the seat tube and the shell. (My theory is that it started as a small, unnoticeable crack as the result of a singularly unpleasant 30+mph crash and slowly extended itself untill the BB wobbled so much that I finally noticed it.) Well, that and the shop let me buy one that was too small. But it was a great bike to ride. Looked good, too. Kind of like yours. Only solid read.