An auxiliary wheel mechanism 151 of a two-wheeled vehicle disclosed herein includes an auxiliary wheel 1, a saddle support member 7, a transmission member 9, and an auxiliary wheel urging member 23. The auxiliary wheel 1 is supported by a vehicle body 11 to be located on a side of a rear wheel 13 and to be movable between a retracted position retracted from a road surface 17 and an operative position where the vehicle body 11 is supported against the road surface 17 so as not to tilt. The saddle support member 7 is provided on the vehicle body 11 and supports a saddle 27 such that the saddle 27 is movable backward and forward. The transmission member 9 transmits a backward and forward movement of the saddle 27 to the auxiliary wheel 1 such that the auxiliary wheel 1 is located at the retracted position when the saddle 27 is located at a front position, and the auxiliary wheel 1 is located at the operative position when the saddle 27 is located at a rear position. The auxiliary wheel urging member 23 urges the auxiliary wheel 1 toward the retracted position. Accordingly, it is possible to achieve the auxiliary wheel mechanism that is for the two-wheeled vehicle and enables a rider to move an auxiliary wheel between a retracted position and an operative position without a manual operation of the rider.

A bicycle bearing system comprising: an integrated cup, the integrated cup having an outer diameter; a plurality of rolling elements configured to abut and rotate against a first race groove located on an inner surface of the integrated cup; a second race groove configured to abut and rotate about the plurality of rolling elements, the second race groove located on an inner surface of the inner race, the inner race having an inner diameter; where the rolling elements do not have a separate outer race, but rather the inner surface of the integrated cup acts as the outer race to the rolling elements; and where the rolling elements, integrated cup and inner race are axially locked when assembled as a single cartridge unit due to the geometry of the rolling elements, first race groove and second race groove.

A unidirectional rotary bearing contains a bearing body, multiple rollers, two rotatable driving rings, and at least two homing springs. The bearing body includes an internal surface and two peripheral surfaces, the internal surface has multiple receiving grooves each having an engagement segment and a disengagement segment, and each peripheral surface has a circular groove. Each of the multiple rollers is columnar and has a diameter which is more than an engaging depth of the engagement segment of each receiving groove of the bearing body and is less than a disengaging depth of the disengagement segment of each receiving groove of the bearing body, and each roller has two drive extensions. A diameter of each of the multiple apertures is more than each of the two drive extensions and is less than the diameter of each roller.

A load cell for determining a radial force acting on a crankshaft includes a receiving sleeve for receiving a ring of a bearing; a fastening ring for attaching the load cell in a transmission housing; axial support areas provided on the fastening ring for axially supporting the ring of the bearing; and measuring regions for receiving radial forces of the receiving sleeve and which connect the receiving sleeve with the fastening ring, wherein strain sensors are attached to at least two of the measuring regions; and wherein the measuring regions comprise measuring lugs formed as angle brackets.

A bicycle bearing system comprising: an integrated cup, the integrated cup having a non-flanged outer diameter; a plurality of rolling elements configured to abut and rotate against an inner surface of the cup race; an inner race configured to abut and rotate about the plurality of rolling elements, the inner race having an inner diameter; wherein the rolling elements do not have a separate outer race, but rather the inner surface of the integrated cup acts as the outer race to the rolling elements; wherein the rolling elements' sizes are maximized to the limitation that the non-flanged outer diameter is smaller or equal to a first maximum diameter, and wherein the rolling elements sizes are maximized to the limitation that the inner diameter is greater or equal to a first minimum diameter.

A one-way bearing, a bearing assembly, and a free-wheeling mechanism for a bicycle are disclosed herewith. The bearing assembly, in one aspect, includes a one-directional bearing having an inner and an outer race, the one-directional bearing including a sprag clutch mechanism. The bearing assembly, according to this aspect, further includes a first thrust bearing and a second thrust bearing, wherein the inner and outer races of the one-directional bearing are formed to retain one or both of the first or second thrust bearings, and a one-directional bearing mechanism located between the inner and outer races. In at least one aspect, the inner race has a flange extending in a radially outward direction, the sprag clutch mechanism abuts the flange on an inner axial side of the flange, and the flange abuts the first thrust bearing on an outer axial side of the flange.

A shaft characterized by its length to diameter ratio being less than about 1.75 having a drive connection at one end where the wall thickness of the shaft is selected to be thick enough to avoid ellipticalization strain error in torsional measurement of less than 5%. One specific application is for a crankset spindle that can be used to measure a cyclist right, left, and total leg torque.

An auxiliary wheel mechanism 151 of a two-wheeled vehicle disclosed herein includes an auxiliary wheel 1, a saddle support member 7, a transmission member 9, and an auxiliary wheel urging member 23. The auxiliary wheel 1 is supported by a vehicle body 11 to be located on a side of a rear wheel 13 and to be movable between a retracted position retracted from a road surface 17 and an operative position where the vehicle body 11 is supported against the road surface 17 so as not to tilt. The saddle support member 7 is provided on the vehicle body 11 and supports a saddle 27 such that the saddle 27 is movable backward and forward. The transmission member 9 transmits a backward and forward movement of the saddle 27 to the auxiliary wheel 1 such that the auxiliary wheel 1 is located at the retracted position when the saddle 27 is located at a front position, and the auxiliary wheel 1 is located at the operative position when the saddle 27 is located at a rear position. The auxiliary wheel urging member 23 urges the auxiliary wheel 1 toward the retracted position. Accordingly, it is possible to achieve the auxiliary wheel mechanism that is for the two-wheeled vehicle and enables a rider to move an auxiliary wheel between a retracted position and an operative position without a manual operation of the rider.

A load cell for determining a radial force acting on a crankshaft having a receiving sleeve for receiving a bearing ring and a fastening ring for attaching the load cell in a transmission housing. Axial support areas are provided on the fastening ring for axially supporting the outer ring of the first bearing. Moreover, measuring regions for receiving radial forces of the receiving sleeve are provided which connect the receiving sleeve with the fastening ring. Strain sensors are attached to at least two of the measuring regions.

A drive unit of an electrically assisted bicycle includes a movement restrictor to restrict the movement of a first bearing relative to a housing along a thrust direction. A first end surface of the first bearing is farther outward than a second end surface along the right-left direction. The housing includes an abutting portion that abuts the first end surface of the first bearing, and a groove that is farther inward than the abutting portion along the right-left direction. The movement restrictor includes the abutting portion, the groove of the housing, and an elastic member fitted in the groove.