All sealing surfaces for gaskets must be clean and flat to make a proper seal, sometimes non-hardening sealant is necessary.Fits for Honda:S65 Sport - 1965-1969ATC70 - 1973-1974C70 Passport - 1980-1983C70K1 - 1972-1973 - No alternator seal includedCT70 Trail - 1976-1982 + 1991-1994CT70HK Trail 70H - 1970-1973CRF70, CRF70F - 2004-2008SL70K Motosport - 1971-1973XR70R - 1997-2003Installation Tips:Press your seals in straight with a seal driver or a socket with a slightly smaller OD than the seal. Both surfaces must be free of dirt to create an oil tight seal.