Nā hiʻohiʻona o nā mīkini helical:
1. I ka wili ana i na mea ea o waho, ua hiki mai ka hoohuli ana ma ka aoao ku e, i ka wa e wili ai i ke kaa o loko me ka mea hana o waho, ua like ka huli ana ma ka aoao hookahi.
2. Pono e mālama i ka nui o nā niho ma kēlā me kēia mīkini i ka wā e hoʻopaʻa ai i kahi mea nui (loko) me kahi mea liʻiliʻi (waho), no ka mea, hiki i nā ʻano keʻakeʻa ʻekolu ke hiki.
3. ʻO ka mea maʻamau e hoʻokele ʻia nā mea hana o loko e nā mīkini waho liʻiliʻi
4. Hāʻawi i kahi hoʻolālā paʻa o ka mīkini
Nā hoʻohana ʻana i nā mīkini kūloko:planetary gear drive of high reduction ratios, clutches etc.