Premium auto parts maker for exotic cars and bikes


Parts now available for your beloved bicycles!


For Cyclists Who Want To Stop Losing 25W Of Power Or More!

Carbon Dry Japan (CDJ) Big Pulley kits are now in store for Shimano and Campagnolo rear derailleurs!

CDJ Big Pulley Kit (BPK) has some advantages.

1) Pedaling with the BPK feels lighter than with a normal derailleur because the friction loss is decreased. Several customers reported that their average speed increased more than 2km/h by their cycle computer.

2) Usage of the Outer/Low (big chainring and rear innermost cassette gear) is smoother than with a normal derailleur. Normally, it will be quite difficult to use gear combinations like this with a normal rear derailleur setup. When riding uphill, once you change from the big chainring to the smaller one, it also usually causes you to shift to another gear on the cassette to get to a ratio or cadence that you like. This frequent and futile action will cost you time loss and tiredness. So the BPK makes things a breeze for you.

3) Both outer and inner CFRP (dry carbon) plates not only give you drivetrain rigidity but are also beautiful to look at. Different cage and pulley colours are also available to suit your preference. This may require a pre-order, so if you have colours other than black that you'd like, please contact us at: [email protected]

4) CDJ also offers you the Middle cage BPK which is suitable for wide range gear ratio when you want to use gear ratio capacity of more than 33T. For example, if you'd like to use 50/34T front with 11/32T rear to have 37T total capacity, and you should use the middle cage BPK. So you can choose it depending on where or how you ride.

5) You will experience an obvious distinction. Enjoy riding your bike with Carbon Dry Japan's Big Pulley Kit!!

PULLEY; 15T / 11T combination
AL 7075 machined
Ceramic bearings
Black or Gold anodized

CAGE; Dry carbon twin plates 2 mm thickness,

*Derailleur is not included.
*A longer chain may be required.
*Installation should be done by a skilled mechanic.