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A process for manufacturing a bicycle chain drive which utilizes a crank which is cold formed as a single piece with integral splines for engaging a sprocket wheel when the sprocket wheel is mounted in driving relationship with the crank. A cold forming process which can be used for producing the cr

A process for manufacturing a bicycle chain drive which utilizes a crank which is cold formed as a single piece with integral splines for engaging a sprocket wheel when the sprocket wheel is mounted in driving relationship with the crank. A cold forming process which can be used for producing the crank includes several stages of upsetting to form the journals, the splined sprocket flange, and an adjoining collar for aligning the sprocket. After those elements have been formed the pedal receiving ends are formed by another upsetting process after which they are drilled and tapped. Then the arms are bent to form the finished crank which is assembled to the sprocket.

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A process for making from steel rod stock a bicycle crank having two crank arms connected by a crank shaft and having means arranged to engage a sprocket wheel in driving relationship with the crank, comprising the step of: cold forming a single piece of said rod stock to form said crank by forming

A process for making from steel rod stock a bicycle crank having two crank arms connected by a crank shaft and having means arranged to engage a sprocket wheel in driving relationship with the crank, comprising the step of: cold forming a single piece of said rod stock to form said crank by forming two crank arms and cold forging a connecting crank shaft, with integral splines on said crankshaft for engaging said sprocket wheel.