Odd oiling problem...

The tank did not leak prior to the cleaning.

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Testimony of how fine of wear particles the filters pass. Corrosion of with good oil and not water layer, hm, Famous spot for fatigue cracks from the bad idea bottom fixing bolt. Just use a rubber ring pad [strades the mount boss] slightly compressed next time or get CNW kit.

I guess brass brazing is the correct repair for pinholes in steel?

yes. Dereck

it is not rocket science. the trouble is either a bad oil pump as dyno dave pointed out or a plugged passage. simply remove the timing cover and oil pump and blow through the oil holes as a test and see what you get there. if all is well have a look at the pump.

pete.v said:

However, I would still want to identify my original problem.

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FWIW here is the oil tank with pinholes in the bottom.
It did not leak prior to cleaning the insides.
The bottom mount is still good.

Success...!

Well, thanks to all the comments and suggestion the bike is now running properly again.
The problem was, as suspected, blocked/restricted suction oil passage from the crankcase bottom pickup hole
to the oil pump scavenge side.

I was able to remove both grub screws with the engine in the frame (front of engine and below timing cover).
I removed the oil line junction block from the crankcase and then shot solvent and air through the holes.
There was some debris that dribbled out but nothing that a magnet picked up. I ran a wire through the drilled passages
to confirm that I got all the way to the end of the drilled oil ways.

This external passage cleaning is not a permanent fix of course. The proper fix will be to re-locate the sump pickup point as shown in previous replies. But that will involve splitting the cases. And thanks for the explanation of how the
Old Britts case modification uncovers the new rear oil pickup point.

This work allowed me to learn many things. I have avoided the potential disaster if the oil tank had started leaking through the pin holes. I also replaced the 3/8" oil lines ($5/foot!) and improved the oil tank bottom rubber mount by getting rid of the rock hard original part replaced with a thick rubber donut. A nice feel to the oil tank mounting now.
I would like to replace the original slot head 5/16"x18 grub screws with an easier to remove recessed hex head type as I intend to do an oil change and drain through the drilled passages too.

Thanks again to the forum!