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New Crosser 2005

Exchange relay

Even those who are familiar with the subject are surprised: The Japanese have obviously not written off the two-stroke crossers for a long time. Yamaha, for example, donated the two 2005 models
with two-stroke engine, the YZ 125 and the YZ 250, even an exclusive new aluminum frame. Unlike the sturdy bridge frames on the Hondas, the Yamaha layout is more like that of conventional steel frames, but with sturdy square profiles. The light metal work of art should be around two kilograms lighter than the steel frame of its predecessor. Yamaha proclaims that with this construction they want to get the well-known good compromise between stiffness and flexibility. Whether and when the four-stroke engines will get the aluminum chassis remains to be seen.
Even with the engine of the 125, no stone was left unturned, here another 1700 grams were saved. Overall, the 125 should be a whopping four kilograms lighter than the 2004 model and almost at the weight limit of this category. The same applies to the 250, but the drive has only been changed minimally. Both four-stroke engines, both the YZ 250 F and the YZ 450 F, will remain with the previous steel frames and will start the new year with only minor modifications.
Suzuki enters with a brand new 450cc four-stroke. Tea R.Technically, the M-Z 450 largely corresponds to the machines successfully used in the World Cup. In contrast to the RM-Z 250 ?? Incidentally, the larger radiator for 2005 and a ge-
got separated cover for the oil filter ?? the big machine has a strong aluminum bridge frame in the style of the Honda Crosser. The dohc engine, in turn, is more similar to the Yamaha engine, but of course only has four instead of five titanium valves. Bore and stroke are 95.5 times
62.6 millimeters in the usual short-stroke ratio that enables high speeds. The crankshaft space is sealed off by a diaphragm valve and the oil is stored in the gearbox. This enabled the crankshaft to be positioned low, which saves overall height. The mixture is prepared by a 40 mm carburetor. Because Suzuki attached importance to a beefy torque curve, a four-speed transmission is sufficient. The landing gear
is equipped with Showa spring elements. The two two-stroke engines enter the 2005 season with a slightly facelifted look.
Kawasaki obviously wants to bring a 250cc two-stroke with a brand new engine in addition to the revised 125cc. The 450 series with aluminum frame, which was already used as a factory machine in Japan, will, contrary to expectations, not be released before 2006. The project, which was in the final stage of development, was stopped at the last moment because the overall performance of the four-stroke model, which this time was not in Cooperation with Suzuki ent-
was not yet entirely satisfactory. The little four-stroke, still one
Joint production with Suzuki and technically identical to the RM-Z 250, only slightly changed.
Honda has worked hard on the 450 series for the coming model year, which, like last year’s CRF 250 R, will now have the fourth generation aluminum frame. This is narrower, especially in the area of ​​the swing arm mounting. There are also further modifications to the chassis
like a new, lighter swingarm. The total weight of the large CRF is reduced by around 1.5 kilograms. The engine, previously the measure of all things, remained practically unchanged. Slightly narrower coolers should improve the seating position. The 250cc oven-stroke was more about giving it more torque. Therefore, Honda designed a cylinder head with new ducts in which a camshaft with modified cam profiles rotates. gt

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