77mm Cylinder Piston Gasket Top End Rebuild Kit For Zongshen 177 ZS177 NC250. Fit for Zongshen NC250. Fit for MIkilon 250cc. Fit for Kayo T6 K6 250cc. If your cylinder blows through, the compression is too low, or even a piston seizure has occurred, then this kit is exactly the right thing for you.
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