SEPTEMBER 2012 / MOTOCROSS ACTION 95
FIRST AND FOREMOST, IS THE 2013 KTM 250SX BETTER THAN THE 2012 KTM 250SX? A: Yes, wholeheartedly yes. It is hard to keep track of all of the changes that KTM keeps making to the 250SX two-stroke. But, the changes they made for 2013 are all on the good side of the ledger. To understand the changes to the 2013 model, you need to trace the last four years of the 250SX’s development. Q: WHAT WAS NEW ON THE 2010 KTM 250SX TWO-STROKE? A: Equipped with no-link, single-sided rear suspension, the 2010 wasn’t all that different from the 2009. The major changes from 2009 to 2010 were a reinforced cylinder head, 1.8 kg/cm2 radiator cap (it was 1.4 in 2009), increased wall thickness in the exhaust pipe (from 0.80mm to 1.00mm), two-bolt triple clamps (the 2009 model had three bolts on the bottom clamp), 22mm offset (from 20mm), and a stiffer shock spring. Q: WHAT WAS NEW ON THE 2011 KTM 250SX TWO-STROKE? A: Although it still had a no-link PDS rear-suspension system in 2011, KTM engineers redesigned the cylinder porting (with a 1mm-lower exhaust port), reconfigured the power-valve flapper spring (from 2mm to 1.8mm wire diameter), installed keystone rings (with a slight taper on the top side for better reliability), made a new exhaust pipe (targeting improved bottom end), outfitted the 250SX with a new silencer (2mm-larger core), developed a wraparound silencer mounting system (that allowed more flex), and eliminated the silencer’s large star-shaped nut (that had the irritating habit of falling off). Sadly, they added the ill-conceived nylon shock preload ring. Q: WHAT WAS NEW ON THE 2012 KTM 250SX TWO-STROKE? A: The big news for 2012 revolved around the all- new rising-rate linkage rear suspension (it was only new to the two-strokes, as it had appeared on the KTM four- strokes in 2011) and a new frame to go with it. Every part of the rear suspension was new, including the top Q: