Okay, up front I know that I was stupid. I just changed the filter and fluids on my Uly. Then, after only two quarts of Amzoil 20-50 synthetic, I ride it down the road for 20 minutes at 45-60mph. I know it was hot, because the fan was screaming when I stopped. So... if I open it up, how much in the way of shavings is too much? Can I use what is normally clinging to the plug magnet as a gauge? I am such a moron. Thanks.