A motor unit includes a case, a motor, an input shaft, an input body, an output body, and a speed reducer mechanism. The input shaft penetrates through the case in an axial direction and is arranged to be rotatable. The input body is disposed along an outer peripheral surface of the input shaft and rotates along with the input shaft. The output body is arranged along the outer peripheral surface of the input shaft to be rotatable and receives rotational force from the input body. The case includes a first bearing, a second bearing, and a third bearing. The first bearing is located at one end in an axial direction and supports a rotary shaft unit including the input shaft, the input body, and the output body. The second bearing is located at the other end in the axial direction and supports the rotary shaft unit. The third bearing is located between the first bearing and the second bearing in the axial direction and supports at least one of the input body or the output body.

An auxiliary power device adapted for use with a bicycle includes a drive unit, first and second one-way transmissions that are adapted to be mounted in a bike frame of the bicycle, a crankshaft and a transmission sprocket. The first one-way transmission is connected between the drive unit and the transmission sprocket. The second one-way transmission is mounted between the crankshaft and the transmission sprocket. When rotation of the transmission sprocket is driven by the drive unit via the first one-way transmission, the second one-way transmission is idling. When rotation of the transmission sprocket is driven by the crankshaft via the second one-way transmission, the first one-way transmission is idling.

A bicycle frame including a down tube, a saddle tube, and a top tube is disclosed. The top tube comprises a first section which, starting from the saddle tube, is oriented in an ascending orientation. Thereby, a space between the down tube, the saddle tube, and the top tube is enlarged, so that the bicycle frame can be carried on a person's shoulder in a more convenient manner.

A bicycle frame including a down tube, a saddle tube, and a top tube is disclosed. The top tube comprises a first section which, starting from the saddle tube, is oriented in an ascending orientation. Thereby, a space between the down tube, the saddle tube, and the top tube is enlarged, so that the bicycle frame can be carried on a person's shoulder in a more convenient manner.

A drivetrain assembly comprises a bottom bracket shell defining a front axis, a dropout defining a rear axis, a chainstay member attached to the dropout and the bottom bracket shell, a front sprocket and a rear sprocket, and a chain or belt including a bottom section extending from a first contact point between the chain or belt and the front sprocket to a second contact point between the chain or belt and the rear sprocket. The chainstay member fixes the dropout relative to the bottom bracket shell, such that a chainstay length is non-variable, and such that the chain or belt has a predetermined tension defined by a midpoint of the bottom section being vertically displaceable only by a maximum vertical extent within a predetermined range upon application of a predetermined load at the midpoint of the bottom section.

A fastening system configured for fastening a device to a hollow component having two holes situated opposite one another. The fastening system includes a first screw that has a head and that is designed to be guided through a first hole of the holes, and a sliding sleeve having an outer diameter that has a tolerance. The sliding sleeve is designed to accept the first screw at the second hole of the holes. An outer diameter of the sliding sleeve is displaceable in the axial direction of the first screw due to a clearance fit.

A fastening system configured for fastening a device to a hollow component having two holes situated opposite one another. The fastening system includes a first screw that has a head and that is designed to be guided through a first hole of the holes, and a sliding sleeve having an outer diameter that has a tolerance. The sliding sleeve is designed to accept the first screw at the second hole of the holes. An outer diameter of the sliding sleeve is displaceable in the axial direction of the first screw due to a clearance fit.

A vehicle includes a forward frame portion, a rear frame portion, and a motion control system that movably interconnects the forward frame portion and the rear frame portion. A forward acceleration of the rear frame portion resulting from a driving force imparted by a wheel supported by the rear frame portion imparts a first force onto the motion control system that counters a second force imparted on the motion control system by an acceleration of a payload supported by the forward frame portion as a result of the forward acceleration.

A vehicle includes a forward frame portion, a rear frame portion, and a motion control system that movably interconnects the forward frame portion and the rear frame portion. A forward acceleration of the rear frame portion resulting from a driving force imparted by a wheel supported by the rear frame portion imparts a first force onto the motion control system that counters a second force imparted on the motion control system by an acceleration of a payload supported by the forward frame portion as a result of the forward acceleration.

A training bicycle with a removably attachable pedal unit enabling adjustment of chain slack by a simple method is provided. The detachable pedal unit is configured to enable attachable/detachable connection of a pedal crank to a bicycle body. The pedal unit includes a unit body having a unit connector for rotatably retaining and fastening to a bicycle body a pedal crank axially supporting a chain wheel. A unit receiving member fixedly installed on the bicycle body to interconnect with the unit connector. A sliding adjustment mechanism provided on the unit receiving member and the unit connector to vary and fix mutual fore-aft connection position of the unit receiving member and the unit connector in order to adjust fore-aft connection position of the bicycle detachable pedal unit relative to the bicycle body and thereby adjusting the chain tension.