The KX/RM proves to have the best chassis, as most of our test riders chose it as their favorite in the handling department.
The new fork is sweet and soaks up most everything thrown its way. When votes were tallied at the end, the test crew liked the Yamaha settings the best overall. The bike is smooth and controlled through the rough stuff and whoops," commented Bent Line. The good suspension performance translates into solid handling characteristics and the riders said it is a good compromise of stability and turning prowess. Some testers, however, feel the YZ feels wide between their legs and cramped. Adjustable handlebar clamps could remedy this problem.
One of the things we are bummed about is Yamaha's decision to wait until next year (presumably and hopefully) to reroute the front brake line like the rest of the manufacturers. Honda's patent on the design ran out this past year, so Suzuki and Kawasaki followed Red's lead with the same direct and shorter design. But Yamaha didn't, and unfortunately, its front brake just isn't as good as the others. It's mushier and doesn't feel as consistent and, consequently, the YZF is at the rear in the braking category.
Overall, the YZF is still a sweet machine, but it was a sitting duck target for the others to shoot at. Think about it this way: How could the other manufacturers have this long to make their 250cc 4-strokes and not be better in some ways? A lot of used, dissected and hammered YZ250Fs are sitting in dark corners of warehouses at Honda, Kawasaki, and Suzuki.
Kawasaki KX250F/Suzuki RM-Z250
The spawn of a collaboration between Kawasaki and Suzuki, the KX250F and Suzuki RM-Z250 are nearly identical twins. The chassis is Kawasaki's contribution, Suzuki designed the motor, Kayaba provides the suspension, and Kawasaki builds them. It's a beautiful little "nuclear family." The only difference between the bikes is the shape of the radiator shrouds, the graphics, and the color of the plastic. That's it. The motor, jetting, suspension settings, measurements, you name it, are the same.
The Kawasaki/Suzuki pumped out the most horsepower with an impressive 34.3.
The four-titanium-valve, DOHC motor utilizes the same bore and stroke numbers as the Yamaha YZ250F, at 77mm x 53.6mm, but no other Japanese manufacturer can implement a five-valve design if they desire, as Yamaha owns the Japanese patent on the design for now. Like the Yamaha, the mill shares its oil with the transmission, but unlike the Yamaha, the oil is entirely held in the motor with none in the frame. One small problem with the Kawazuki motor is that the oil filter and water pump share the same outer cover. Unfortunately, this means that every time you change your oil filter, you have to drain the coolant. That's a poor design that the aftermarket companies have already begun to remedy.
The frame is a perimeter-design like most Kawasaki MXers and utilizes a square-tube aluminum subframe. The layout and riding position feel very KX-ish, which means flat and roomy. This layout can also be altered with the adjustable, rubber-mounted handlebar clamps â€“ one direction moves them forward for bigger riders and vise versa for smaller fellas and gals. An automatic decompression system aids in starting along with a clutch-perch-mounted hot-start lever (all of the contenders feature the same starting set-ups).