yes abc engines are tight.run one lean when its cold, and watch it seize. Same when its hot. Do you know why a motor sags in the air or on the ground when too lean? the piston has grown larger than the cylinder, and is fixing to seize. also, call yamaha, and tell them that the aluminum piston we run, dosent go with the crhome plated brass cylinder they ported for me. We also run k and b sportster type cylinders,(no sleeve) that are all cast aluminum, with a solid aluminum piston. Its not brain surgery, its the same thing. I am through with this, and its not any help to the man above that cant figure out his problem. your engines have no compression cause theyre worn out. good luck, and dont fry your engines.
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