Abagibeli abaningi abasha abasanda kuthenga i-ibhayisikili lezintabaAngazi umehluko phakathi kwejubane elingama-21, ijubane elingama-24, kanye nejubane elingama-27. Noma yazi nje ukuthi ijubane elingama-21 lingu-3X7, ijubane elingama-24 lingu-3X8, kanye nejubane elingama-27 lingu-3X9. Omunye umuntu ubuze nokuthi ibhayisikili lasezintabeni elingama-24 lishesha yini kunebhayisikili elingama-27. Eqinisweni, isilinganiso sejubane sinikeza abagibeli amathuba amaningi okukhetha. Ijubane lincike emandleni omlenze womgibeli, ukukhuthazela kanye namakhono akhe. Uma nje unamandla amakhulu, ijubane elingama-21 alisheshi kunebhayisikili elingama-24! Ibhayisikili lasezintabeni lingagibela amamayela amangaki?
Ngokombono, ngesikhathi esifanayo sokuhamba ngesivinini sokuhamba, ibhayisikili elinamajubane angu-27 lizogijima ngokushesha kunebhayisikili elinamajubane angu-24. Kodwa eqinisweni, ngesilinganiso segiya eliphezulu, ukuhamba ngesivinini kuzoba nzima kakhulu, kanti ukuhamba ngesivinini kuzokwehla ngokwemvelo. Uma ukuhamba ngesivinini kwehla, ijubane lizokwehla ngokwemvelo. Ngezinye izikhathi abanye abaqalayo bathenga amabhayisikili asezintabeni bese bethi, “Ibhayisikili lami lihle, kungani kunzima kangaka ukulihamba ngesivinini?” Isizathu ukuthi akakhethanga isilinganiso segiya esifanelana naye lapho egibela.

Okokuqala ake sibheke umehluko phakathi kwe-21-speed, 24-speed kanye ne-27-speed:

isondo lochungechunge kanye ne-crank enamajubane angu-21 48-38-28 isondo elindizayo 14~ 28

Isondo eliyi-chainwheel kanye ne-crank enama-speed angu-24 42-32-22 isondo eliyi-flywheel 11~ 30(11~ 32)

Isondo eliyi-chainwheel kanye ne-crank enama-speed angu-27 44-32-22 isondo eliyi-flywheel 11~ 30(11~ 32)

Isilinganiso segiya yinani lamagiya ahlukaniswe ngenani lamasondo ajikelezayo

Isilinganiso segiya esiphezulu samajubane angu-21 3.43, isilinganiso segiya esincane 1

Isilinganiso segiya esiphezulu samajubane angu-24 singu-3.82, isilinganiso segiya esincane singu-0.73 (0.69)

Isilinganiso segiya esiphezulu samajubane angu-27 4, isilinganiso segiya esincane esingu-0.73 (0.69)

Kulokhu singabona umehluko phakathi kwazo. I-27-speed kanye ne-24-speed inesilinganiso segiya esikhulu noma esincane kune-21-speed, okungakwenza ugibele ngokushesha futhi kukwenze ugibele kancane. Ngenxa yokuthi i-chainwheel enamajubane angu-24 ayifani ne-21-speed, i-chainwheel encane ingathola isilinganiso segiya esilula, okuyinzuzo enkulu uma ukhuphuka. Ibhayisikili elinamajubane angu-24 lingafinyelela isilinganiso sokudlulisa esingu-1.07 noma ngabe lisebenzisa isilinganiso sejubane esingu-2X1. Uma i-flywheel ingu-11~32, lingafinyelela isilinganiso sokudlulisa esingu-1 (isilinganiso sokudlulisa esincane se-21-speed singu-1). Ngakho-ke inzuzo ngaphezu kwebhayisikili elinamajubane angu-21 le-24-speed ayikho nje kuphela egiya elisheshayo, kodwa itholakala kakhulu egiya elihamba kancane, okwenza kube lula futhi kube namandla kakhulu ngawe ukugibela emigwaqweni yezintaba. Umgibeli omusha ucabanga ukuthi ibhayisikili elinamajubane angu-24 lishesha kunebhayisikili elinamajubane angu-21. Mhlawumbe bambalwa abantu abahlukanisa inani lamazinyo e-crank ne-cassette ngayinye ukuze babone ukuthi umehluko uyini.

Ngokuphathelene nebhayisikili lasezintabeni elinamajubane angu-27, isondo lalo elijikelezayo livame ukufana nelena elinamajubane angu-24. Umehluko ukuthi i-crank enkulu kunazo zonke engaphambili ilungiswa kusuka ku-42 kuya ku-44, efanelekile kubantu abanamandla amahle ngokomzimba. Ibhayisikili lasezintabeni elinamajubane angu-24 noma ibhayisikili lasezintabeni elinamajubane angu-27 umehluko phakathi kwezingxenye ezahlukene zebhayisikili ezithuthukisiwe zaba amamodeli angcono ngebanga lalo.