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Ridge reaming does not solve cylinder wall taper and ovality. Installing new rings in an engine, lke that, is a waste of effort. The cylinders are no longer perfectly parallel and they are not perfectly round. It would be better to check the ring end gap on the original rings and if they were in specs clean and reinstall. The same ridge that develops as an engine wears also wears the outer upper point of the top ring. While ridge reaming keeps the top ring from breaking as it contacts the ridge that you have removed.
New rings can seal a tapered bore but they are expanding and contracting on every up and down movement of the piston. New rings will not seal a bore that has ovality wear. Of course a tapered bore will always have a ridge.
The development of better alloys combined with far superior lubricants allowed engine life to triple over the past 5 decades, even with perfect maintenance. Reduction in emissions, fuel injection, lead free fuel, better ignition and other factors were also contributors.
If there is no measurable wear in the cylinder walls, no ridge, no taper, and no ovality, and the cylinder is factory original then the engine should never have needed a rebuild in the first place. According to your statements that is the norm on high mileage but well maintained D series Honda engines that were not abused. The vast majority of engine die of abuse and neglect.
The exception to that rule is a car that sat a long time and had rusty cylinder walls due to open intake and exhaust valves in a humid environment.
When Chevrolet first offered the small block in 1955, intital customer feedback showed extreme oil consumption to the tune of a quart in 200 miles in a brand new car. GM's solution was to pour Bon Amid down the carburetor to add an abrasive to help with ring seating!
regards
Mech
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