|It was overdue. The Yamaha WR450F had grown old and was virtually forgotten against a backdrop of stunning new off-road bikes from Europe. Finally, a new WR is here, and it’s one of the most impressive bikes of the year. The Yamaha isn’?t just a YZ450F with lights and a big muffler. That was the old way of doing things. In fact, the new bike is nothing like the YZ450F, and instead is more heavily influenced by two other Yamaha products: the YZ250F and the original WR450F. The short form is that it’?s the 450 motor in the YZ250F frame, with a new Keihin fuel injection system. There are a number of reasons that Yamaha didn’t go with an off-road version of the bike that James Stewart rides. Cost and fuel capacity were on the top of the list. But another big factor might be the perception that the YZ250F handles better than the 450. Yamaha engineers wanted to get rid of the heavy feel that the old WR had, and the addition of fuel injection usually adds weight.|
Most people feel that the new-for-2012 YZ250F perimeter aluminum frame is nothing short of brilliant. As far as the motor goes, the new WR has fuel injection a Keihin capacitor system, just like the YZ. If you wanted to strip it down, you could remove the electric starter, the battery and a few other items and have a bike that weighs no more than a motocrosser.