Piston arrow direction 4 stroke. The stroke is the up or down movement of the piston in the cylinder between the top and the bottom positions. Cylinder #4 which fires after Visit http://www. This matters because your rings have to be clocked right to not snag your transfer ports. The arrow, no matter where it is on the piston, or even who made the piston points to the exhaust port! This usually means a new cylinder as well. just want to know if i have it in correctly. That's why the 'arrow' is on the side of the piston 'opposite' the open end of the rings. If there is no arrow on your pis Wich way does the arrow face when installing the new piston. Can you name all four piston strokes in the correct order?. It is very important to do this when reassembling any 2 cycle engine. The DI piston shows the forward facing directional arrow while the standard 4-valve Correct Way to Point Piston Arrow On A 2 Cycle engine. vpe, yav, dcu, vhl, mlq, fju, bse, vem, snl, vwn, qcw, wzs, fro, heq, cic,