Abstract: An attachment (4, 30, 40) for connecting a first bicycle (1) to at least one second bicycle (2), the bicycles (1, 2) being connected in the direction of motion, and the attachment (4, 30, 40) being rotatably connected to at least one bicycle (1, 2) and extending in a substantially fixed length transversally to the direction of motion, between its respective mounting points (8, 12, 34, 42, 44, 46) on the first bicycle (1) and the second bicycle (2), respectively.

Abstract: An attachment (4, 30, 40) for connecting a first bicycle (1) to at least one second bicycle (2), the bicycles (1, 2) being connected in the direction of motion, and the attachment (4, 30, 40) being rotatably connected to at least one bicycle (1, 2) and extending in a substantially fixed length transversally to the direction of motion, between its respective mounting points (8, 12, 34, 42, 44, 46) on the first bicycle (1) and the second bicycle (2), respectively.

Abstract: The combination of a rotary tool and a drive therefor, the tool having a conical taper between 60.degree. and 120.degree. to chamfer or remove burrs from machined workpieces. The tool comprises a casing containing a motor for rotating the tool, the motor having a drive shaft connected for rotation to the tool, and the tool having a shaft coaxial with the drive shaft. The drive shaft and the tool shaft are elastically connected for axial sliding movement of the tool shaft relative to the drive shaft against a force urging the tool shaft in a direction away from the drive shaft. The drive shaft is splined, and the tool shaft has thereon a splined member surrounding and engaging with the splines of the drive shaft.