2008 KTM 250SX

2008 KTM 250 SX: Refining KTM's New-Generation Two-Stroke

The 2008 KTM 250 SX was primarily a refinement of the heavily redesigned 2007 model rather than another new generation. KTM retained the new-generation frame, compact 249 cc engine, five-speed gearbox and WP suspension package introduced the previous year, concentrating on detail changes intended to make the motorcycle smoother, easier to control and more consistent over a full moto.

The engine continued with its 66.4 x 72.0 mm bore and stroke, Keihin PWK 36 mm carburettor and exhaust power-valve system. KTM focused on refining throttle response and the transition into the strong midrange rather than chasing a completely different power character. The 250 SX remained extremely fast, but the aim was to make that power easier to meter at corner exits and on rough tracks. Owners dealing with worn original fuel-system parts can compare alternatives using the MXOwners carburettor reference.

The WP suspension also received ongoing development. The 48 mm closed-cartridge fork provided 300 mm of travel, while the linkless PDS rear shock delivered approximately 335 mm. Correct fork servicing and rear sag remain particularly important on this generation, and the MXOwners fork oil reference is useful when returning modified or neglected forks to a known baseline.

At roughly 95 kg without fuel, the 2008 250 SX remained exceptionally light for a full-size 250 motocrosser. Its hydraulic clutch, strong disc brakes and broad two-stroke power made it a serious alternative to the increasingly dominant four-strokes of the period. Accurate premix remains essential for long-term engine life, and the MXOwners premix calculator can help prepare the correct 1:60 mixture.

Historically, the 2008 model is important because KTM continued investing in two-stroke motocross development while several competitors were reducing theirs. Rather than allowing the 250 SX to become an ageing specialist machine, KTM kept refining the engine, chassis and suspension. That commitment would eventually leave KTM in a commanding position as demand for modern two-strokes returned.