…give the bike character. At the heart of the WR426 is a motor which retains the 95.0 x 60.1mm bore and stroke and the 12.5:1 compression ratio of its YZ426 counterpart. A quintet of titanium valves keep fuel and spent gas heading in the right direction while a 39mm Keihin carburetor provides the proper…

…steel frames are the lighter than the alloy-framed pair. Part of what makes the Yamaha so light is the loss of fifth gear from the shorter-stroke YZ426 model. Further reducing weight, as well as making the engine quicker revving, are the lighter-weight titanium valves, short skirt pistons, and a lighter…