I will bet you are running a K&N type filter and if you are skimping on the oil treatment you have found your source of silica. They flow more air but they also flow more dirt
I agree. I do oil analysis and the additive package with Redline 50WT has been good every time I checked. I run the oil for at least 1/2 season then have it analyzed. The oil itself would easily run a whole season, the problem I've had is high silica (dirt). After the last analysis, I replaced the oil fill cap o-ring which was hard as a rock and suggested as a source of the contamination (my air intake system is tight as far as I can tell). We'll see if it stays cleaner when I do another sample after the season.
Ron, I don't think the 50WT oil is slowing you down
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