Its cold in here, someone left the door open!

With the boxer, and 10:1 fuel oil mix, surprising how much oil gets past the followers and valve guide clearances... I think bert does the oil mode to renew the oil through the rocker chests by rerouting the crankcase breather through the rocker chests and then vents the rocker covers, one or both, depends on how you route the breather tubing... I still run my boxer on glow fuel, so no real need to make that mod... but I have had a look see, and the way I usually do it on the gas 4 strokes is, I create a few thou flat down the cam followers using a honing stone, to give a bit of passage for blowby to work its way up the pushrod tubes, and then just vent the rocker covers... it gets rid of the external tubing, and tidies up the appearance... but basically it keeps a small amount of oil moving through the rockers... Gas engines running with the leaner oil mix ratios, it can be beneficial... but with a 20% oil content, the oil will find its way into every nook and cranny.