( 3) Muffler. Last year’s KTM mufflers were odd ducks. Each model’s muffler was different. The 250SXF muffler was 40mm shorter and had a wire screen; the 350SXF muffler had an inverted, perforated cone in the muffler; and the 450SXF had two perforated cones in its muffler. MXA learned early on that using the shorter, less- restrictive 250SXF muffler improved throttle response and bark (without drastically increasing the sound). For 2014, all three KTM four-strokes come with the 250SXF muffler (40mm shorter and with a wire screen only). Q: WHAT HOMEGROWN SOLUTIONS DID KTM FORGET TO PUT IN THE 2014 MODEL? A: Local racers learn by experience—trial and KTM’s errors. Here are the mods they wish KTM would have borrowed from their modified bikes. Spokes. In truth, there is nothing wrong with KTM’s spokes; it is the rims that are suspect. Never go to the starting line without checking the spokes, especially the spoke next to the rear rim lock. Odds are good that it will be loose. If you don’t want to risk wheel failure, you can lace up the existing spokes and hubs to Excel A60 or D.I.D. rims. Preload ring. It seems as though KTM keeps spec’ing their flawed nylon shock preload ring in spite of the fact that it was a bad idea that hasn’t gotten any better with time. When you crank the preload down on the shock spring, the nylon threads deform and seize the ring in place. Shift lever. When the shift lever is in the stock position, it is too low, and when you move it up one notch, it is too high. We place our shift levers between two blocks on a hydraulic press and bow the middle of the shift lever to raise the tip. Air filter. Never stick the air filter into the airbox without double-checking to make sure that the filter’s back edge is sealed against the intake tract. This would be easy to fix at the factory, with a more distinctively shaped filter or a lip on the back side to notch the filter cage into. Shift shaft. Unlike on a Japanese-built bike, KTM’s shift lever is slipped onto a tapered spline with a bolt holding it at the end of the shaft. This creates several problems. First, the tapered shift shaft gets smaller as it moves outward, which means that if the shift lever does get loose, it is on a downhill run to falling off. Second, with the bolt at the end of the tapered shaft, the rotational inertia of every downshift puts a torque load on the shift shaft, which loosens the shift-shaft bolt. Honda, Yamaha, Suzuki and Kawasaki use a straight- splined shaft with the bolt in a notch in the shift shaft. Because the bolt is at a 90-degree angle, the shift lever cannot fall off unless the shift-lever bolt falls out.
450SXF 2014 KTM 450SXF: Although it looks mildly updated on the spec sheet, KTM’s engineers put a lot of thought
into upgrading the 2014 model. Now, if
KTM’s suspension designers would
work a little harder then everything
would be hunky-dory.