From:Rob Olsen
Subject:RE: An oil starvation FWI... Date:Tue Jul 3 16:18:09 2012
Response to:4159
The oiling system is a metered system using restrictor plugs to evenly distribute oil. In addition the bypass allows oil to drip onto the timing gears and reduce pressure. The inlet elbow also has a restrictor plug that can be opened up to 5/16 for racing.
With all things in balance the system works quite well set up like the factory, make a change and you need to compensate all the way down the line. Restictor plugs were approx .040, which I find can potentially plug over time.
You can never fill up that timing cover with that big hole in front.
Oil flow is the key to removing heat,

Indian used the bearing shell as a restrictor. Check the size difference between Indian and Henderson.

HD 20W50 oil is an oil designed for engines, not gears or clutch's. HD supplies primary oil and gear oils for their application. In addition HD does not make oil. They contract out to the cheapest supplier. Consequently the base stock is loaded with enhancers & slip modifiers and other junk to keep the cost down. HD oil is a poor choice in my opinion.