Home owner vs. Commercial

[bertsmobile1]

I was working on Honda engines in the early 1970's that ran the camshaft(s) directly in the aluminum head or cover. Those never gave any trouble until you ran low on oil or missed an oil change.

Exactly the point, ran fine unless you ran low in water or oil or missed an oil change , so you end up blaming yourself for the trashed head .
Where as a rolling element bearing or gunmetal bush would not have been affected any where near as much.
The rolling element bearing would have run till after there was not enough oil to float the big ends without problems .

 

[Hammermechanicman]

Back when the Briggs 5hp was THE engine for WKA stock engine class some guys bought the 130212 engine with the bushed PTO side crank bearing instead of the 130232 engine which had the ball bearing on the PTO side of the crank because it was cheaper. Geared properly the engines topped out at 6000 rpm. In one day of racing they could egg out the bearing surface in the case from the side load of the chain. I wouldn't build the 130212 engines for guys because they wouldn't last. The 130232 would last a whole season if you double bushes the valve guides. The crank was never a problem with them.