Imibhede yesibhedlela ebhukwini yimibhede yezokwelapha esebenzisa ama-cranks ezandla ukukhulisa wonke amazinga embhede, kanye nezingxenye zekhanda nezinyawo zombhede. Imibhede yesibhedlela ebhukwini iyisisombululo esisebenzayo esifanelekayo esigulini esinomnakekeli noma onamandla okusebenzisa i-crank yesandla ukukhulisa nokwehlisa umbhede.