Pulled from wikipedia: GS - Gran Sport, used to indicate a road going Suzuki standard motorcycle, the only model that still uses this designation in the Suzuki line up is the GS500.Sport V-twin
But then again, what does GSXR stand for? It may just be a model name.
Don't like all the Harley names actually have meaning? FLTR is something like flathead touring.... raccoon? I dunno.Its all just model designation. Doesnt really stand for anything. Just like GSX-R. You could go back to the early GS models then they went to DOHC and became GSX models then they had 'racier' versions that got the GSX-R designation. Most manufaturers do it. What does CBR, YZF, ZX, FLTR stand for? Nothing really if you are looking for put words to each of the letters