A52 is the number for the late model tomos case.

An A52 case could be either an A35 or A55


  • cylinders are stamped A5
  • black or silver cast iron cylinder, head says TOMOS
  • 2.5hp, stock reeds, dellorto SHA
  • angled exhaust port on cylinder


  • cylinders are stamped A55 or A56
  • silver aluminum cylinder with nikasil lining
  • 3hp, piston port, dellorto PHVA
  • less angled exhaust port