For most motocross racers, the Mellow Map would only be used on rock-hard or slippery surfaces, because it takes the bark out of the engine however, because of the massive midrange hit of the TC250, running the Mellow Map is more common than you would think. It has two settings one hash mark is the “Aggressive Map” and two hash marks is the “Mellow Map.” If you activate the Mellow Map, the power delivery will be smoothed out for ease of use. The Husqvarna has a two-position map switch on the right side of the handlebars. If you unplug the KTM’s white wire, you get the “Mellow Map.” If you plug it in, you get the “Aggressive Map.” But that is neither here nor there, because we aren’t talking about the 2020 KTM 250SX two-stroke here. Since it is the only white connector under the frame, it is easily identified. Located under the fuel tank is a wire that is fitted with a white male/female plastic connector. When you find the best spot on the dial, mark it with a paint pen so you can find it easily.įor some unknown reason, the 2020 Husqvarna TC250s comes from the factory with a click-style switch that allows TC250 owners to access two different ignition maps, while KTM owners don’t get the map switch (although they can access the second ignition map by unplugging one wire).
#2017 tc250 stock pro taper handlebars full#
The full range of the Husqvarna power-valve adjuster is six turns. Be willing to turn it both clockwise and counterclockwise just to ensure that you are getting what you want. We turn it in 1/8-turn increments, always keeping track of which way we turned it. The power-valve adjustment is very sensitive. While the larger-diameter main power-valve spring determines when the power-valve flapper begins to open, the smaller color-coded auxiliary springs determine how fast it opens and at what rpm it will be fully open.Īs a rule, most MXA test riders prefer to stick with the stock yellow auxiliary spring however, we love to adjust the power valve by turning the adjuster. Changing the small auxiliary springs can make your exhaust flap snap open quicker (red spring) or open slower (green spring). Your Husqvarna comes with green, yellow and red auxiliary power-valve springs. The Kreft Moto Power Dial allows you to adjust the Husky TC250 powerband by hand. The Husqvarna power valve adjuster is the brass dial below the water pump over. Most riders should find the sweet spot between 1 and 2 turns out. You get started by turning the power valve adjuster all the way out (counterclockwise) and then turning it in 1-1/2 turns. Even better, Kreft Moto sells an adjustable power-valve adjuster called the Power Dial that allows you to make instantaneous adjustments (even on the side of the track) by hand. Plus, if you use a screwdriver, the proper size Robertson wrench, which is available from KTM, Husqvarna and Nihilo Concepts, might never fit again. It is important that the flat blade be a perfect fit in the brass dial, because the brass is very soft and can be scarred by a loose-fitting screwdriver. In a pinch, you can use a flat-bladed screwdriver that is the same size as the square adjuster. SOLVING THE MYSTERY OF THE ROBERTSON WRENCHĭid you notice the reference to a “Robertson head adjuster”? Yeah, we don’t have a Robertson wrench either. At 213 pounds the Husqvarna TC250 weighs 11 pounds less than a Husky FC450 four-stroke, 6 pounds less than a 2020 Yamaha YZ250 and one pound more than a KTM 250SX.
#2017 tc250 stock pro taper handlebars manual#
Oh yeah, ignore where your owner’s manual says not to adjust the power valve-obviously the adjuster was put there to adjust. You do not need to loosen the two screws that hold the brass adjuster to the engine (unless the dial is stuck). Want mellower power? Turn the adjuster clockwise for smoother power and a broader range of tractable low-end power. Want more hit? Turn the power-valve adjuster counterclockwise for an aggressive hit and maximum top-end power. Adjusting the preload on this changes when the power valve opens. The main power-valve spring’s preload can be altered by turning the “Robertson head” adjuster in the center of the power-valve spring cap. Husqvarna’s powerband can be controlled by the power-valve adjuster. The ability to vary the size of the exhaust port gives your two-stroke engine broad and usable power from bottom to top. As revs build, the flap gradually opens, expanding the size of the exhaust port for greater top-end power. This helps the engine generate torque at low speeds. At low rpm, the flap is held closed to make the exhaust port smaller. The power valve is a movable flap located in the cylinder’s exhaust port, where burnt gases are flushed out of the cylinder. Husqvarna, in its infinite wisdom, realized that two-stroke owners come in a wide variety of shapes and riding styles, thus the engineers made the TC250 engine tunable via the power valve.
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