On my 2 stroke engine while taking a look at the cylinder ive got maybe a centimeter long scratch on the inside of the cylinder. I can just get my fingernail inside of it and im wondering if i should get it replaced.
Unless it is such a deep gouge that you you can trim your fingernails on it I would not worry about it. Small scratches are not desirable but unfortunately all too common in these engines. They are usually caused by manufacturing debris left inside the engine by the factory. Final inspection/ quality control is still somewhat a mystery to them.
Enjoy riding the engine until she blows, then rebuild it or replace it.
Dude i have ran pistons that looked like i took a rock to the side of the skirt and jugs that looked like i ran 80 grit sand paper down the side together and the motor ran pretty well lol
but yeh unless your going for a high performance race bike dont worry unless the crome os chipping off