its not so much that the CR 500 has less hp but the way the power is delivered. The KX 500 has a nice smooth powerband. The CR 500, without the powervalve, has much more of a hit of power. From something like 3500 to 5000 rpm the power of a CR 500 and KX 500 jump like 20hp but a graph of a CR 500's dyno run shows the slope is much steeper than the KX 500 meaning that all that power is hitting faster and harder. I think this is where people can get into trouble, all that power hitting so fast surely breaks traction and could probably be a handful in the woods but it doesnt worry me any.