The function of the combination of the crankshaft and connecting rods converts the reciprocating of the piston into the rotational of the crankshaft and outputs power.The connecting rod transmits the and power of the piston to the crankshaft which pushes the crankshaft to rotate.The crank bearing receives the force from the connecting rod and converts it into a torque about its own which is then transmitted to the transmission system while driving the valve train and some other auxiliary devices. Diameter: 35-34mm Size: STD (Standard) / +25 / +50 / 75 / 100 Material Type: Forged Steel Fit For: GSX-R1000 K5-K8 2005-2008 GSX-R1000 K9 L0 L1 L2 2009-2012 Compatibility Disclaimer: This is an aftermarket replacement part.Any brand names or model designations mentioned are used solely for the purpose of demonstrating compatibility.