Pedaling with the BPK (Big Pulley Kit) is lighter than normal derailleur because friction loss is decreased. Several customers reported their average speed gains more than 2km/h by their cycle computer.
 
You can use Outer/Low position (front outer gear and rear inner gear) smoother than normal derailleur. Or quite difficult to use this position with normal one. When you ride a bike on the uphill road, once you change front gear to inner then you should also change rear gear. This means frequent and futile action will make you time loss and to get tired. So less the number of times shifting with BPK makes you airily.
 
Carbon cages, both outer and inner CFRP(Carbon Fiber Reinforced Plastic) plates give you not only steady capability but also visually beautiful that makes you a sense of superiority. And you can choose cage color as your preference.
 
CDJ original pulley; AURUM+CF30, a kind of special plastic contains 30% carbon fiber. It’s light but very strong like a metal. Even though almost half of aluminum weight. High noise reduction and low sliding friction. Color is like a dark green with marble.
 
You could use up to 30T rear gear with the BPK, depending on the setting.
 
PULLEY combination; 17T / 12T
 
FIT; SRAM E-tap / Red22 / Force22 
 
CHOISE
CAGE COLOR; Matte / Clear / Red / Blue / Yellow / Green
Added gloss color charge 2,000JPY except for Matte
 
CERAMIC BEARINGS
Hybrid ceramic bearings (ceramic balls with steel housing combination) installed as standard.
Full ceramic bearings are selectable + 6,000JPY
 
REAR DERAILLEUR
Installing the genuine rear derailleur to the BPK is also available when you order. Please allow some days to provide it.