The S3 Thunderbolt sport-touring model was produced from 1997 through 2003, along with a mechanically identical S3T “Touring” model that ran through model year 2000. The 1,203 cc air-cooled V- Twin engine was mounted as a stressed member in a tubular frame. The powerplant output 91 hp (68 kW) in 1997 and jumped to 101 hp (75 kW) in the following years due to revised cam profiles and the new Thunderstorm cylinder heads. While the bike’s overall look was the same throughout the model run, there were significant changes made in 1999 that set it, and later models, apart from the 1997 and 1998 bikes. The early bikes used a rectangular section steel rear swingarm, WP Suspension front forks and rear shock, a Keihin 40 mm CV carburetor, and a Performance Machine six-piston front brake caliper. Beginning in 1999 a new cast aluminum rear swingarm was utilized along with Showa front suspension forks and rear shock. The front brake caliper, while still a six-piston unit, was now made by Nissin. The most technological change came in the new Dynamic Digital Fuel Injection (DDFI) system, replacing the old carburetor. The S3 featured a half faring that surrounded the headlight and gave decent wind protection for the rider’s torso. The S3T model then added lower fairing extensions that gave better wind protection to the rider’s legs. The S3T also featured hard saddlebags that could be color-matched to the bike color and were available in either “wide” for maximum storage, or “narrow” for a lighter feel. In addition to the lower fairings and the saddlebags, the S3T also came with a taller handlebar for a more upright, relaxed riding position. Each of the parts that set the S3T apart were available as accessories for the standard S3 model.[better source needed][23] M2 Cyclone (1997–2002) The M2 Cyclone was produced from 1997 to 2003. It was in the middle of the Buell line up between the puristic S1 Lightning and the more comfortable but heavier S3 Thunderbolt. The S1 Lightning being the fastest and lightest of the bunch but offered a very narrow seat due to its minimalist approach for weight saving in this sport bike. The S3 Thunderbolt was a touring bike that offered a bigger wider seat and more comfortable riding position but was also a heavier motorcycle. The M2 Cyclone filled the gap between the sport and touring models with a bigger seat than the S1 Lightning and lighter and faster than the S3 Thunderbolt. The M2 was only available with the 1,203 cc engine and five-speed transmission. The frame was of the tubular CrMo steel type. 2000 Buell Blast The Blast was Buell’s only model to use a single-cylinder engine. With 492 cc (30.0 cu in) displacement and 360 lb (160 kg) dry weight, it was their smallest model, often used in Harley-Davidson’s “Rider’s Edge” new rider instruction/ riding schools. This filled Harley CEO Jeff Bleustein’s idea of having a make- specific training bike, since many students end up buying a bike from the dealer where they trained. The Blast came from a quick proof-of- concept at the Buell factory.[10] It originally used half of a Sportster 883 engine. The engine ended up 80 percent over budget and very expensive compared to the higher-technology Rotax engines available from outside the company. Cycle World wrote “Such an overrun would be unheard of from an outside supplier, but when your supplier also owns you, you grin and bear it.” The Blast was ultimately the most expensive development project Buell undertook.[10] Because the engine was overpriced, it ended up making money for Harley while losing money for Buell. It was regarded as a technical success. In July 2009, Buell ran an ad campaign stating that the Blast would no longer appear in their line-up. The ad featured a Buell Blast being destroyed in an automobile crusher. XB-series (2003–2010) 2003 Buell Lightning XB9S 2006 Buell Lightning CityX XB9SX A club racing version of the Buell Ulysses XB12X The XB powertrain still had its roots with the Harley Sportster powertrain, and was designed for both projects.[10] Unfortunately, it was designed by Harley with minimum input from Buell. A turbocharger was to be sourced from Buehl