The stress across a surface element (yellow disk) is the force that the material on one side (top ball) exerts on the material on the other side (bottom ball), divided by the area of the surface.
Overview. The WR450F retails for $8,290, making it the sixth-most expensive 450cc 4-stroke enduro bike of 2013. It comes equipped with a 449cc engine, which is slightly larger than average for a 4-stroke motor.he WR450F retails for $8,290, making it the sixth-most expensive 450cc 4-stroke enduro bike of 2013.
The Ultra Sport is the basic model, with max riding speed of 30 mph, while the Factory steps it up to 34 mph. The Pro Race is the competition board designed for more advanced riders, with a special sport carburetor and a max speed of 35 mph. Pricing for the Jetsurf starts at $10,000.