Valve Chart

NOTES:

  1. Dimensions are in inches, unless stated in millimeters
  2. Stem length measured from inner edge of ground face to tip of stem
  3. Seat angle 45° for all except Minor, which is 60°
  4. Tranco part numbers are usually stamped on the stem next to the collet groove
  5. James part numbers usually cast proud on the surface of the head, often with the letters “VK+”

Collet groove types are as shown below:

Screenshot 2015-08-07 12.39.40