2001 KTM 250SX

2001 KTM 250 SX: The Last Evolution Before KTM's New-Generation 250

The 2001 KTM 250 SX was primarily a refinement of the existing 250 SX rather than a completely new generation. It retained the established 249 cc engine architecture, 66.4 x 72 mm bore and stroke, five-speed gearbox and chrome-molybdenum steel chassis. That makes it an interesting final-stage example of KTM's older 250 platform before the substantially redesigned engine arrived for 2002.

The engine used KTM's Twin Valve Control exhaust system and Torque Chamber to broaden the delivery of a powerful competition two-stroke. Fuel was supplied by a Keihin PWK 38 AG PJ flat-slide carburettor, while the hydraulic wet multi-disc clutch was already one of the features distinguishing KTM from many Japanese rivals. Owners restoring an original machine can use the MXOwners carburettor reference when comparing worn or replacement components.

Suspension consisted of a 43 mm White Power upside-down fork with 295 mm of travel and KTM's linkless WP PDS rear system providing 320 mm. Correct setup remains important on these early PDS machines, and the MXOwners fork oil reference is useful when servicing the original fork.

With a 7.5-litre tank, 21-inch front and 19-inch rear wheels and strong hydraulic disc brakes, the 2001 model was a pure motocross machine. It represents the mature version of KTM's pre-2002 250 SX design: powerful, mechanically straightforward and distinctly Austrian, just before KTM introduced the newer-generation 250 engine that would shape the model through the middle of the decade.