Abstract: An enclosed bicycle drivetrain is provided that produces a range of drive ratios suitable for any riding purpose. The enclosure of substantially the entire drivetrain is made practical by the synergistic cooperation of a planetary drive system using a single chain ring and a streamlined rear derailleur system that separates the tensioning and chain guiding functions of a conventional rear derailleur, allowing the rear derailleur components to remain substantially within the shadow of the outer perimeter of the bicycle frame. The planetary drive system is provided with a unique compound pawl that may be easily disengaged from a planetary ratchet member under full riding loads by the application of a small force to destabilize the pawl. A unique shift buffer mechanism cooperates with the rear derailleur system to buffer and store up to the full range of available shift commands.

Abstract: An enclosed bicycle drivetrain is provided that produces a range of drive ratios suitable for any riding purpose. The enclosure of substantially the entire drivetrain is made practical by the synergistic cooperation of a planetary drive system using a single chain ring and a streamlined rear derailleur system that separates the tensioning and chain guiding functions of a conventional rear derailleur, allowing the rear derailleur components to remain substantially within the shadow of the outer perimeter of the bicycle frame. The planetary drive system is provided with a unique compound pawl that may be easily disengaged from a planetary ratchet member under full riding loads by the application of a small force to destabilize the pawl. A unique shift buffer mechanism cooperates with the rear derailleur system to buffer and store up to the full range of available shift commands.

Abstract: An enclosed bicycle drivetrain is provided that produces a range of drive ratios suitable for any riding purpose. The enclosure of substantially the entire drivetrain is made practical by the synergistic cooperation of a planetary drive system using a single chain ring and a streamlined rear derailleur system that separates the tensioning and chain guiding functions of a conventional rear derailleur, allowing the rear derailleur components to remain substantially within the shadow of the outer perimeter of the bicycle frame. The planetary drive system is provided with a unique compound pawl that may be easily disengaged from a planetary ratchet member under full riding loads by the application of a small force to destabilize the pawl. A unique shift buffer mechanism cooperates with the rear derailleur system to buffer and store up to the full range of available shift commands.

Abstract: The present invention provides a human powered vehicle drive system that includes a vehicle frame, a power system including a pivotable drive lever and a one-way clutch, a neutral shifting system, and a braking system. The drive lever may be coupled to a tension member that is associated with the drive lever and a drive spool, so that power is transmitted from the drive lever to the drive spool via the tension member, and from the drive spool to a driven wheel via the one-way clutch. A drive-ratio shifting control allows a user to vary a drive ratio by translating the attachment point of the tension member to the drive lever up or down the drive lever. A neutral shifting control allows the user to engage and disengage the one-way clutch. The braking system includes a flexible brake linkage routed along the drive lever. The drive-ratio shifting, neutral shifting, and braking controls may all be situated proximate to a drive lever handle adjustably coupled to the drive lever.