Chainsaw Repair

There are some advantages of the chromed piston/bare bore approach:

There is less surface area on the piston, so it makes some sense to give it the harder coating.

The chrome plating will reduce thermal conductivity a bit.

The rings run on the bare cylinder which would seem to be a disadvantage, but in practice does not seem to be a problem.

The worst aspect is if foreign objects get into the cylinder (carbon chunks, etc.), as then they get dragged along the unplated cylinder walls by the piston/ring and plow grooves into it.