Most of you probably remember my post a couple weeks ago about finding sand in my oil filter on my bike and chasing the cause down to find that it entered through the crankcase breather hose. I initially felt that the hose got plugged in a crash and then the dirt was sucked into the motor. I cleaned and flushed the motor and changed the oil several times after I found sand for the first time. All was clean and I felt good about it. I did replace the black hose with a clear one so that I could see if dirt made it into the hose. After a few hard practices and a race this weekend, I changed the oil again. Sand in oil filter!! I removed the clear hose and inspected it. Sand grains have worked there way all the way up to the valve cover. For some reason there is more negative pressure than positive pressure on the breather and even though it feels like it is blowing air, there is suction. I am going to now do what I should have done to start with and put some sort of filter on the end of the breather hose. I have owned two previous YZF's and I have never noticed this. It could be unique to the '06, or with my luck.......just unique to mine.