Box Two-E 9S Drivetrain Bundle w/ Prime 9 Technology
Box developed the Box Two-E system as an e-bike specific drivetrain to offer more robust high wattage strength and a better riding experience. With Box 9 speeds and wide range gearing means less shifting action and more efficiency for the motor. With the 42 and 50 tooth low gears, it’s possible to maintain optimum pedaling cadence while climbing steep hills. By enabling riders a higher pedaling cadence, the electric assist also operates more efficiently and is able to climb without bogging down the motor.
- E-Bike specific drivetrain designed to provide wide gear ratios with reduced shifting
- 454% differential between gear 1 and gear 9
- Easy to use Twin Lever Shifter actuation
- Low maintenance derailleur
- High durability cassette and chain
With the trend to 10, 11, 12 and now even 13 speed cassettes, the gears and chains are getting thinner and more fragile. With a mid-drive motor you need fewer gears but more strength in drive train components. This is something Box noticed and did something about. Depending on the mid-drive motor, you can be putting between two and over ten times the typical human power through the drive train. By taking a step back to 9 speeds, Box was able to beef up the drive-train to withstand these magnified ebike power levels.
Box Prime 9 Compatibility Guide