Damage to the cylinder bore

[Comiemutering]

I've had my Xciting 500 for a few years and I've been maitaing well and has been running great. A few weeks ago I noticed some power loss and started to dig in to find the problem. Long story short, I ended up sticking a camera probe in the cylinder and saw there are some scratches. Can anyone explain why?

 

[WokThisWay]

I've had my Xciting 500 for a few years and I've been maitaing well and has been running great. A few weeks ago I noticed some power loss and started to dig in to find the problem. Long story short, I ended up sticking a camera probe in the cylinder and saw there are some scratches. Can anyone explain why?

yeah, scratches can also be a result of the engine overheating, which causes the piston to expand faster than the cylinder.
This can lead to the piston seizing momentarily, creating scratches or scuffing. Overheating could be caused by a cooling system issue (low coolant, bad water pump), a lean fuel mixture, or a timing issue.
honestly, it's a big red flag that something is out of spec