On May 21, 4:28*am, Brian Whatcott wrote:

...every four stroke has a 2:1 reduction drive built in.
One that's subject to really lumpy loads.
It's called the cam shaft drive. Beefing up this chain
or gear drive would be one way.....
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Dear Brian (and the Group)

I tried this approach some years ago. I used an after-market steel
cam gear for my starting point and came up with approximately 1200
hours as the service-life, indicating a re-build would be required at
the 600 hour mark.

I began by turning the engine over. Upside down, it would require a
pair of out-board oil pumps, one for scavaging the oil from the heads
& crankcase and feeding it to a new oil sump, the second pump drawing
oil from the sump and feeding it to the engine for lubrication,
filtering, cooling and so forth.

The reason for inverting the engine was to give me full access to the
existing oil pump's location. An outboard bearing and thrust assembly
was designed for this opening. The propeller shaft was a spllined
unit, 1.25" in diameter. That part of the project was relatively
straight-forward, using a double-row ball bearing for both thrust &
prop shaft support.

I don't recall the details as to why I gave up on the project but it
had to do with the interface between the cam shaft and the cam gear.
This project was done in the early 1980's.

-R.S.Hoover