Piston ndi kayendedwe kobwerezabwereza mu thupi la silinda la injini yamagalimoto. Mapangidwe a pistoni amatha kugawidwa pamwamba, mutu ndi siketi. Pamwamba pa pisitoni ndi gawo lalikulu la chipinda choyaka moto, ndipo mawonekedwe ake amagwirizana ndi mawonekedwe osankhidwa a chipinda choyaka moto. Ma injini a petulo nthawi zambiri amagwiritsa ntchito pisitoni yosalala pamwamba, yomwe ili ndi mwayi wamalo ang'onoang'ono amayamwitsa kutentha. Pistoni ya injini ya dizilo nthawi zambiri imakhala ndi maenje osiyanasiyana, mawonekedwe ake enieni, malo ake ndi kukula kwake ziyenera kukhala ndi mapangidwe osakaniza a injini ya dizilo ndi zofunikira kuyaka.