I have a 1990 Seadoo St. Now the first thing that runs through your head is"No you don't dummy", but wait! I'm a Seadoo Guy and a good wrench. I have 5 now and have gone through around 20. I repowered this boat recently and could not convince the engine shop that I had the ST. The graphics are original and I even have the original saddle bags that also say ST. The model charts never mention it so I am curious.