SP = Sport Production, and it was a variant of the 900 SuperSport that was only available in North America.
If you’re looking for performance, this was the version of the SS that you wanted, thanks to the wider rear rim, fully adjustable front and rear suspension, aluminum swingarm, carbon fiber front fender/clutch cover, and a full fairing. Despite that, it was still relatively comfortable – a sportbike that you could enjoy every day. In this piece on Cycle World, Peter Egan says that this 900SS is “the used motorcycle you need” and notes that “they made perfectly comfortable long-distance touring bikes, but on winding roads through the Black Hills, they metamorphosed back into sportbikes of deep finesse, with killer, real-world midrange and light, intuitive handling.”
The seller of this example says it’s in mint condition with 8,900 miles, and I’d say it’s well-modified with an Ohlins shock, Oberon clutch slave cylinder, Spiegler stainless steel brake/clutch lines, Woodcraft rear sets, Shorai battery, and a Staintune exhaust. It might make a purist flinch but I think these mods are excellent if you want to enjoy this bike on the road, not just on display. Impressively, the sale includes all paperwork from new, including the original invoice and “every receipt for service and parts since.” Plus, all the original parts are included. It was just serviced and is ready to ride, which I hope the next owner takes advantage of!
Find this SS/SP for sale in Los Angeles, California for $7,000 or best offer here on Ducati.ms.