Kuri revisiyo nkeya, gusubiranamo kwa piston ya moteri biratinda, kandi imbaraga zo gukuramo zo kuvanga imvange muri silinderi ziragabanuka. Muri iki gihe, valve yo gufata igomba gukingurwa igihe kirekire gishoboka, kandi iyo piston yirutse igana hepfo yapfuye ikinjira muri compression, valve yinjira irahita ifungwa kugirango ibuze gaze ivanze gusohoka. Mugihe kamera ifite "ikarishye" yambukiranya ifunga valve yihuta, kamera "umuzenguruko" ifata igihe kirekire kugirango ifunge. Rero, kuri rpm nkeya moteri ikenera kamera "ityaye".

Kuri revisiyo ndende, piston ya moteri isubirana byihuse, kandi imbaraga zo gukurura kuvanga imvange muri silinderi irakomeye. Ndetse iyo piston yiruka igana hepfo yapfuye kandi igiye kwinjira muri compression, gaze ivanze izahita yinjira muri silinderi muri iki gihe kandi ntishobora guhagarikwa. Nibyo, ibi nibyo dushaka, kuko niba byinshi bivanze bishobora gukururwa muri silinderi, noneho moteri irashobora kubona imbaraga nyinshi. Muri iki gihe, dukeneye kugumya gufata valve yo gufungura mugihe piston yazamutse, kandi ntitukayifunge mugihe kiri imbere. Camshaft ya "rounder" ubu iragaragara!

Imiterere ya moteri ya kamera ifitanye isano rya hafi n'umuvuduko wa moteri. Kubivuga mu buryo bworoshye, kuri revisiyo yo hasi dukeneye kamera "ityaye"; kuri revisiyo ndende dukeneye "uruziga".