Originally Posted by BlankCrows

That goes for all of the series except the more expensive racing type bikes. The RX's were sport bikes, and the RX-7 was the top model for those. The Maruishi racing bikes had didn't have number designations.

There isn't much info out there for this brand. They made some nice bikes, but never were as popular as Bridgestone, Miyata, Nishiki, Panasonic, etc. My RX-7 is mid eighties era. Your bike would be late 1980's per the decal font. Go over to vintage-trek.com and you can date the bike using the components from it there.

The OP's bike has those goofy looking Olympic-ish symbols on the top tube, perhaps to lure in triathletes on a budget.