Ko te tikanga o te rakau honoe toru nga wahanga: he roopu tinana, he roopu hono piston me tetahi roopu wīra crankshaft. Ko te miihini hono o te crank te waahanga neke nui o te miihini ki te mohio ki te huringa mahi me te whakaoti i te huringa kaha.

I roto i te whiu hiko, ka huri i te piston hiko waiariki i hangaia e te ngingiha o te wahie ki te nekehanga tauutuutu me te hurihanga crankshaft ki te hiko miihini ki te whakaputa mana; i etahi atu whiu, ka whakawhirinaki ki te inertia hurihuri o te crank me te wīra rere, ka peia te piston ki runga, ki raro i roto i te rakau hono ki te Waihanga tikanga mo te mahi ka whai ake.

Ko te mahi a te miihini hono a crank ko te whakarato waahi mo te wera, te huri i te pehanga roha o te hau ki runga ake o te piston i muri i te tahuna o te wahie ki roto i te taipana o te hurihanga crankshaft, me te whakaputa tonu i te mana.

(1) Hurihia te pehanga o te hau ki te taipana o te crankshaft;

(2) Hurihia te nekehanga tauutuutu o te piston ki te nekehanga hurihuri o te crankshaft;

(3) Hurihia te kaha o te ngingiha i runga i te piston runga ki te taipana o te crankshaft ki te whakaputa i te kaha miihini ki te miihini mahi.