Does anyone know the factory bore size for a 1975 DT 175. The piston is 66 mm

Does anyone know the factory bore size for a 1975 DT 175? The piston is 66 mm.

Wondering how much larger the cylinder is than the piston. Trying to decide whether to replace rings with standard size or bore to . 25. Thanks.

3 comments
  • Standard bore is 66mm

  • The piston is 66. The cylinder has to be larger than 66 exactly for the piston to move. Believe it's 66.04.

  • The bore should measure 66mm and the piston would then measure 65.9 mm you need a good dial bore and caliper