What caused this

the 72nd goon
Edited Date/Time 9/18/2017 8:05am
Kx 144 piston after 4 hrs. The tip of the spark plug is fused into the top.

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H4L
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H4L 9/16/2017 9:13pm
9/16/2017 9:13pm
It looks like a lean jetting cond. or higher octane fuel needed or a combination of both. If your running higher comp. in the engine you need to run higher octane fuel. A 2 stroke engine will melt a cast piston if the jetting is lean & using a lower octane than what the motor was set up for.
the 72nd goon 9/17/2017 4:20pm
9/17/2017 4:20pm
H4L wrote:
It looks like a lean jetting cond. or higher octane fuel needed or a combination of both. If your running higher comp. in the engine you...
It looks like a lean jetting cond. or higher octane fuel needed or a combination of both. If your running higher comp. in the engine you need to run higher octane fuel. A 2 stroke engine will melt a cast piston if the jetting is lean & using a lower octane than what the motor was set up for.
Thank you
Dusin791
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Dusin791 9/17/2017 8:55pm
9/17/2017 8:55pm Edited Date/Time 9/17/2017 8:57pm
Could be using the cheaper spark plug?
Kyle220
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Kyle220 9/17/2017 9:25pm
9/17/2017 9:25pm
The crank seal behind the stator can cause that too, could be sucking air in somewhere.

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Bhack711
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Bhack711 9/18/2017 8:05am
9/18/2017 8:05am
How many hours on the crank? A friends bike had this problem. It turned out that the crank bearings were worn cause it to be a big "longer" than spec, and the piston hit the head.

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