Word forms: (regular plural) crankpins
noun (Automotive engineering: Vehicle components, Engine, transmission, and exhaust) A crankpin is the part of the crank of a crankshaft to which the connecting rod is attached. ⇒ Crankpins transfer up-and-down motion between the crankshaft and connecting rod. ⇒ The big end of the connecting rod is connected to the crankpin of the crankshaft by way of a bearing. ⇒ Connecting rods typically have two-piece crankpin bearings for connecting the lower end of the rod to a crankpin of a crankshaft.
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