I changed my oil today on my 450. This is the second oil change and it has 4.1 hrs on the motor. When I removed the the filter, I found sand in the oil!!! There was a noticable amount present, but it was not plugged with sand. I sat there puzzled as to how sand was inside of my motor. Then I realized what had happened. I had a bad crash on the bike at about 2.5hrs. The bike went down hard on the left side. I quickly removed the breather hose from the top of the valve cover and i found sand traces at the valve cover. I removed the valve cover to inspect inside. There is no sand inside the valve cover except for a few grains near where the hose enters, but this is where it entered. I checked my valves while it was apart and all is in spec. Just from a visual inspection the cams do not look damaged. The bike runs great. My concern: Any amount of sand in an engine is a very bad thing......even a grain or two. My brand new bike has been run with sand in the crankcase. How worried should I be? Should I have faith that the passageway from the vent led to the bottom of the crankcase where the oil was quickly picked up and cleaned by my oil filter?? Should I have faith that my SCOTT'S filter trapped all of the sand before it could do much damage in the 1+ hour that the bike ran after this? or Should I begin gathering money together to pay for a new engine as this one will shortly fail? I have a sick feeling in my stomach.