WITH THIS PISTON YOU MUST USE A HEAD (AND_CRANK) FROM A (CT70 1969 TO 81),(XL,SL,CL OR ATC70) MUST BE USED WITH THIS PISTON KIT!!!!!!!!!!! OR OUR OLD_STYLE BARE_HEAD = (OLD_70_DOME) THIS WILL ONLY WORK IN OUR 52MM BIG CYLINDER STOCK HONDA CYLINDERS CAN NOT BE BORED OUT THIS BIG!!!! @ 52MM_PISTON_KIT (OLD_70_DOME) (SHORT_ROD) (SHORT_CYLINDER) (100042) (S1409) 100042 (S1409)