Very light scoring on new piston. Looking for advice.

[Fatherwheels]

This. If it was me before I even considered running a after market cylinder I would chamfer the ports.

An absolute must to ensure the ports are chamfered, you can see looking in
the exhaust port there is vertical plating pointing straight upwards,
there would be a nice clean line there if there was a chamfer.
I know most will disagree, but I would take it apart and tidy up
the ports, it will only take a few hours with hand tools.

 

[Dreffan]

When I mix my gas at 12to1 for my old Pioneer Da it lubes the engine just fine and if anybody trys to tell me I am running too lean a mix and I will probably burn out my saw due to the lean mix are dreaming in full color.Answer me this If i Screw the high speed needle in till the saw will barely run your saying it will seize from lack of oil because it is set too lean I think not.
If I follow your reasoning which is the oil is to thick to flow past the high speed needle what happens does all the oil pile up and fill the gas line and gas tank with the excess oil that can not get past the high speed jet because only the gas can get threw.
Many many more motors were killed from lean mixes than from rich mixes I have never saw a motor killed from too much oil.
No matter what oil to gas ratio you use you always tune your saw for the CONDITIONS THAT DAY.
Kash

I have but it was for a odd reason. Sold a Stihl bg50 to a customer and filled the tank with Stihl fuel. Showed him the oil though he did not speak English I thought he understood. He did not!! Put the entire container for one gallon in the tank and topped off the tank with gas. Did not survive till the end of the tank. Seen blowers last longer with no oil.