nut house

Discussion in '2-Stroke Engines' started by canalcat, Apr 17, 2015.

  1. canalcat

    canalcat Member

    I measured my head bolts at 1 and 3/4 inches square .Is this48cc? Also how tight do I set the nuts? I have a small gasket leak! Thx anyone!

  2. crassius

    crassius Well-Known Member

    if I did the metric conversion right, it is a 48cc with 40mm piston

    clean surfaces & gasket well, turn gasket over so compression ring on bottom of head gets a new bite, torque is 8ft/lbs, but try to get it to about 10% over & see if it holds

    otherwise, you'll need a new gasket
  3. MotorBicycleRacing

    MotorBicycleRacing Well-Known Member

    The 48 cc has 6 mm head studs.
    Yes, a 6 mm stud is the same size as the motor mounting studs and exhaust studs etc.

    If your head has 8 mm studs it is a 66 cc
    can you tell the difference between a 6 mm and a 8 mm stud?

    The distance between the holes on a 66cc head gasket is bit over 1 3/4"

    The distance between the holes on a 48cc head gasket is bit over 1 5/8"
  4. crassius

    crassius Well-Known Member

    there is a diff if you measure between holes or between centers of studs