So, I just picked up a new 2014 YZ450F. New to Yamahas, but not new to four strokes...haven't even ridden it yet, but I was looking through the manual and in the section where it discusses the oil change steps, which seem very simple and straightforward, it also shows a couple of extra steps that I never took on other four strokes. There an oil strainer that it says to check, as well as loosening an oil pressure check bolt to ensure that the oil pressure is coming up. Do people actually do these two steps with every oil change? What is an oil strainer? Is this similar to the oil screen on a KX that does not need to get checked as often? I can see where it is and it certainly looks easy to check, but I am just not sure what it actually does. Just thought I would ask before taking these extra steps if they are not totally necessary.