Posts
3
Joined
9/26/2025
Location
USA
Hi all,
I’ve recently finished restoring my 1991 kx125 (which has around 3-4 hours on the engine) and I took the expansion chamber off to clean some brackets and I found some areas of the cylinder that look like the cross hatching has worn off in between the ports. The ring gap is spot on, cylinder was replated back to stock with a standard piston and it’s running the stock carb setup with 32:1. Any help would be great. Not sure if that’s normal as I don’t have much experience with nikasil engines.
Thanks, Leo
Also I just wanted to add that I GENTLY used the tip of a screwdriver to check for scoring and the “worn” areas feel smooth
The crosshatching extends through the “scuffing.” But the picture may be deceiving and reflections in the cylinder can create all kinds of illusions. I wouldn’t worry about it but if you want to make sure pull the cylinder.
As long as the piston is in the right way in the bore, checked the end gap during assembly, you're probably fine.
Was the plating matched to the piston?
Did you check the piston:bore clearance?
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