enlarge Whizzer "H" head bolt holes to 5/16

Discussion in 'Whizzer Motorized Bicycles' started by jameyslane, Jan 31, 2012.

  1. jameyslane

    jameyslane New Member

    Is it ok to enlarge the Whizzer "H" head bolt holes to 5/16 so it can be used on a "J" model cylinder?

  2. Quenton Guenther

    Quenton Guenther Motored Bikes Sponsor


    Just be careful of bolt length, as some of the "H" heads have different heights of bolt ramps.

    The very early "H" heads used 2 different lengths of head bolts, and mixing them up would break off some of the cylinder fins. The later "H" heads used the 5/16" bolts, I think after motor number H-120,000.

    The "H" & "J" heads have the same combustion chamber.

    Have fun,
  3. jameyslane

    jameyslane New Member


    Thanks Quenton........I appreciate you answering my question.