Since this thread is still running I might throw in some thing else. I'm fourth generation in the family doing residential tree care. So,some one in the family has been running chainsaws, since there were chainsaws. I worked for my Dad from the late 60's to the mid 80's. In that time period the logic on bar oil swung from one extreme to the other. One line of thought was that a thick oil stuck to the bar longer and lubricated better. The other line of thought was a thin oil flew off the end of the bar and "carried heat" off the bar better and faster. Both sides has slews of scientific data to back them up. We adjusted our chains so you could pull up on the chain with two fingers till the drive link was just clear of the bar on top, or maybe even sagging a wee little bit on the bottom of the bar. Run a tank of oil per tank of fuel, should be good. The three Homelites in this picture were running when I took the pic, and they all have the original bars on them. Twenty years commercial use and another 20 of me abusing them. They all sit on a shelf in the garage now, but 40 plus years of mostly 10w30, Joe.