Cracked cylinder


Local time
1:44 AM
Sep 24, 2023
Lexington, SC
I was riding along yesterday and suddenly lost all power on the bike. I got home, took it apart and did a little bit of inspecting, and I found a crack in my cylinder head. This one came from Amazon seller was Seeutek. The stamp on the cylinder says BZON. not really sure what that means.


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I agree. I’ve already swapped the jug, piston, & rings out for new ones that I already had on hand. Took it for a ride when I got it done and started the break in process. I’m not really happy about all that but at least I was able to keep the bike going. It’s not only mode of transportation. And the seller is sending me replacement parts as well. I don’t know anything about porting but I did take a needle file and I cleaned up the transfer ports and the intake and exhaust ports very lightly before I put it all together and also conditioned piston rings before I put them on. I’m hoping this doesn’t happen again. still a rookie, clearly.
I would use a lighter grit sandpaper to round the port edges by hand to help protect the plating around the corners (and prevent ring snags). I prefer to use a diamond burr on my rotary tool flex shaft, but I am fancy like that.
I have a friend on Facebook that’s trying to sell me a ported cylinder that he did himself. I’m about to post some pictures. I was wondering what you guys thought about this & if it is worth paying $60 for


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