Join Date: Nov 2009
Location: Lander, Wyoming
You are correct that with the Stock KLR oil filtration cap & cavity there is always some un-filtered oil squeezing between the cap & cavity and going into the 'clean-side holes' at 6:00 & 11:00.
The minimal clearance between the cap & cavity mostly reduces the chance of anything large enough to lock-up the bottom rod bearing to near impossible. The potential issue with crumbs, slivers & chips is mostly during oil filter changing time.
Kawasaki moved the 'clean-side' crankshaft oil port to safer locations on Newer Designed Engines like the KLX / KX F series.
Brent Kelsey & Others,
Operating the KLR engine at Half a Window of oil is akin to operating an automobile engine at the "L" on a dipstick, about 20% LOW on volume. The Low mark on the KLR window is about 35% LOW on volume. This means that 65-80% volume of oil has to do 100% of the work, which makes it degrade even faster in a motorcycle engine with all of the those transmission gear teeth literally chewing up the oil additives & oil base stock molecules verses an automobile engine with only 2 timing gears.
Chains & Sprockets in the KLR and other engines are NOT harsh on engine oils, but unfiltered dust particulates & excess steel polishings ARE Harsh on Chains & Sprockets.
With high quality engine oils, kept FULL, a KLR can easily run 5000 miles between oil changes. There is an "OIL Analysis Thread" on this forum.
Modify at "YOUR OWN RISK"!
Still riding my 1987 KL650-A1. 85,000+ miles & counting