I see that happen often when people try to rebuild their SMC with a kit, rather than purchasing the entire unit.
I believe you are correct thinking that the bore is scored, corroded, or damaged.
Like Dave said, its better to have hands on, to see if things are/were done correctly.
I wish I had a dime for every member who told me his bike had no leaks, or was not leaking coolant, before we started tearing it down to find the truth