What bueller said. To be honest dont let size fool you. My cr250 hangs just fine. Sure when we hit upon road the 450 can walk but on single track that big bike gets dusted. A four stroke will be a little more forgiving throttle wise but to be honest there is very few better feeling than railing in then power band of a two stroke. I just bought a 04 cr 250 and rebuilt the top end for about 300 bucks. Doing the valves on a four stroke will be much much more. Maintenance on two strokes really isn't much. No oil changes. Just gear oil. New spark plug every now and then depending on how much you ride. Besides that just don't over rev too much and you are good. And yes Aaron I know how to ride. Been on two wheels for as long as I can remember. From a small town in the desert. You ever want to ride real trails come out here to nv and I will show you some amazing trails. But leave those street tires at home. You need knobs out here.