Bicycle driving system and kit

A auxiliary drive kit for a pedal assembly of a bicycle, wherein the kit is provided as a modular part, the kit comprising:

• a drive unit comprising a housing, end caps at opposite sides of the drive unit, a motor unit having a stator, a rotor and an output shaft and accommodated in the housing, and a first stage deceleration unit having an input part connected coaxially to the output shaft of the motor unit to transmit a drive force from the motor unit to the first stage deceleration unit in the housing, and an output part, and the first stage deceleration unit has an input part and an output part, the input part of the first stage deceleration unit being coaxially connected to an output shaft of the motor unit to transmit drive force from the motor unit to the first stage deceleration unit in the body;
• a mounting unit configured to secure and hold the motor unit and the first stage deceleration unit on a bicycle body, the mounting unit comprising a pair of or multiple pairs of support plates, extending away from a spindle of the pedal assembly, having different spacings and/or a selection of extension lengths, wherein the mounting unit is configured to hold the drive unit selectively within a space defined by a triangular frame of the bicycle or outside of the space;
• and
• a second stage deceleration unit arranged external to the drive unit and detachably mounted on the first stage deceleration unit for connection to the pedal assembly, and configured to transfer a drive force from the output part of the first stage deceleration unit to chainrings of the pedal assembly, and the second stage deceleration unit comprising a transmission wheel set having a selection of deceleration ratios,
• wherein the mounting unit further comprises an adaptor disposed between the support plates and the drive unit, the adaptor being configured to adjust a spacing between the support plates and the drive unit to adapt for an axial length of the spindle;
• wherein the motor unit and the first stage deceleration unit each have a cylindrical wall of substantially the same outer diameter and are separated by a partition wall, an output shaft of the motor unit extending through a hole in the partition wall into a housing portion of the first stage deceleration unit, the cylindrical wall and the end caps are detachably connected by fasteners;
• and
• wherein the drive unit, the mounting unit, and the second stage deceleration unit are each provided in a modular manner and are detachably mountable relative to one another.

A bicycle drive system for mounting to a bottom bracket of a bicycle, comprising:

• a drive unit including a housing which houses a motor unit and a first stage deceleration unit coupled coaxially to an output shaft of the motor unit;
• a mounting unit configured to secure the drive unit to the bicycle;
• and
• a second stage deceleration unit external to the drive unit and operatively connected to a pedal assembly of the bicycle;
• wherein the mounting unit comprises spaced-apart support plates extending away from the bottom bracket which houses a spindle of the pedal assembly, and an adaptor disposed between the support plates and the drive unit, the adaptor is configured to adjust a spacing between the support plates and the drive unit;
• wherein the mounting unit is configured such that the spacing between the support plates is adjustable to adapt for different axial lengths of the spindle;
• and
• wherein the drive unit, the mounting unit, and the second stage deceleration unit are each modular components that are detachably mountable relative to one another by fasteners.