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motocrossactionmag.com

TEN THINGS THE FACTORIES NEED TO ADDRESS

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(1) KTM exhaust. It’s not often you have to remove an exhaust, but when you have to perform this task on a modern KTM four-stroke, it turns out to be a nightmare. The stock KTM head pipe and mid-pipe are one piece. This makes it impossible to get the exhaust system off the bike without removing the shock. All the popular aftermarket KTM exhaust pipes come in three pieces—head pipe, mid-pipe and muffler. KTM and fellow traveler Husqvarna need to switch to three-piece exhaust systems.

(2) Vulcanized grips. When it comes time to put new grips on a Kawasaki, good luck. The stock grips are vulcanized to the throttle tube and won’t come off no matter how much contact cleaner and muscle you use. The only way to remove KX grips from the throttle tube is with a razor blade—and even that is not very helpful. To save time and fingers, we buy an aluminum throttle tube.

(3) KX450F chain guide. MXA has been complaining about the KX450F rear chain guide for years. It is not only worthless but dangerous. We have had test riders wear all the way through the buffer and the metal until the chain comes out the bottom. Kawasaki has reworked its chain guide several times but never solved the problem. Before hitting the dirt, we call TM Designworks to replace all of our KX chain guides with its bulletproof design.

(4) Husky airbox. When Stefan Pierer (owner of KTM) bought Husqvarna back in 2013, he decided to make the Husky’s engine and chassis identical to KTM’s; however, something had to be done to differentiate Husqvarna power from KTM power. The solution? Suffocate the Husqvarna engines. Drill out the Husky airbox if you want it to run like a KTM.

(5) KTM shock collar. While it is true that KTM has modified and upgraded the nylon preload ring on its shocks over the years, it is still a pain to live with. The nylon threads don’t work well with the high temps of the shock body. When you try to spin the warm nylon threads, they deform and lock against the shock body’s threads. This causes the nylon preload ring to stick. Since MXA test riders check their preload every race, we are often stymied by frozen threads. You cannot hit the KTM preload ring with a hammer and punch, because the nylon notches will chip off. Come on, KTM, think of a new idea instead of Band-Aiding a bad idea.

(6) Twice pipes. We understand aesthetics, but we also understand performance. Since every other bike on the market has single-sided exhausts that make the same or more horsepower while weighing as much as three pounds less, Honda’s twice pipes are a negative. They add several pounds of top-heavy weight. They cost more to repair and add unneeded complexity. MXA has had great luck with single-sided aftermarket CRF450 exhausts. As for Honda’s claim that twice pipes equalize the weight of the left and right sides of the bike, that’s hokum. See page 124 for proof.

(7) Brake fluid. The stock Kawasaki and Honda front brake fluid seems to be only a distant cousin of high-quality brake fluid. We don’t know what they install in their brake systems on the production line, but whatever it is, it doesn’t work very well. The stock brakes are weak and spongy. After the first break-in ride, we bleed the questionable CRF and KX-F brake fluid and replace it with high-temp Maxima Dot 4 Racing brake fluid.

(8) Radiator caps. The 2017–’18 Honda CRF450 and 2008–’17 Suzuki RM-Z450 will spew out coolant if the engine gets remotely hot. This is due to the 1.1 kg/cm2 radiator caps. The 1.1 radiator cap doesn’t have sufficient pressure to keep the coolant from boiling. The simple solution is to raise the cooling system’s maximum operating pressure by using a 1.6 kg/cm2 radiator cap (like Kawasaki) or 1.8 kg/cm2 cap (like KTM and Husky) to prevent boil-over. This solution should come straight from the factory.

(9) Showroom feel. Long ago, manufacturers found that more people bought the bikes that felt best on the showroom floor. Potential buyers push the suspension up and down, pull in the clutch and twist the throttle. Forks that feel plush, a clutch that feels effortless and an easy-to-twist throttle are marketing men’s dream selling points. But ask yourself this: how will a clutch that works based on spring pressure actually perform on the track if your six-year-old kid sister can pull it in on the showroom floor? MXA test riders burn through a Suzuki clutch while doing practice starts. An easy fix is to put stiffer clutch springs in—not that the marketing team would approve.

(10) Yamaha YZ250. We’re not asking Yamaha’s engineers to redesign their decade-old YZ250 smoker—although they should if they want to promote the sales of new YZ250 two-strokes instead of used ones. We’re only asking for small refinements to make it relevant in the two-stroke world again. A Pro Circuit or FMF YZ250 pipe and silencer can add 2 horsepower and 1 pound of torque to a YZ250 with ease. Why doesn’t Yamaha install a stock OEM exhaust system that does the same thing? That one simple change would put the YZ250 on par with the KTM 250SX in the pony wars.

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