ok thanks for the help I will test this weekend and get back to you!its hard to tell how it sounds in a video....do these things so we can determine the health of your engine.
leak test with a 2 stroke leak tester....if it holds 7 pounds of air for a half hour without leaking its good there
compression test....should be around 120 psi
answer these questions and get back to us
just a new pistonWas it fresh bore also, or just new piston?
What brànd ?
just a new piston
Right I see what your saying thanksproving my point even more, should have bored the cylinder to match the piston. Did you buy a cheap cylinder kit with stock bore? If so, there again lies the problem. If you bought an oem cylinder, how are you sure the piston was the right size?