From a performance standpoint, it's hard to outgrow the CRF150R. But as racers get bigger, they need a slightly bigger CRF150, and that's where the Expert comes in. It has bigger wheels, a slightly higher seat, and a slightly longer swingarm. But it still has all the same intense performance thanks to a powerful Unicam. four-valve engine, fully adjustable Showa. suspension, and championship-bred componentry throughout.