CRANKSHAFT

Crankshaft function is to convert the piston motion into movement of the play (machinery) and forward coupling force (moment of force) produced a motor to power the switching device to the wheel. Crankshaft bearings are generally held in a fixed glide on the crank. Crankshaft bearings are usually called the main bearings.
Type crankshaft used on motorcycle engines are:
1. Type of built-up used in small type motor has a cylinder number one or two
The burden of work on the crankshaft is:
- Load torque (torque)
- Load curved (bent)
- Load centrifugal
2. Type of "one piece", is used in large type motor that has a lot of cylinders.

Picture 1. Type crankshaft One Piece

For a single-cylinder motor in crankshaft axis (usually in front of the crank pen) is placed as a counter-balancing the weight of the crank cycle when the piston under pressure of work. But many of the motor cylinder, a pen attached to each other crankshaft balance. Weight of counter weight approximately equal to the weight of the piston rod at the crank plus the weight entirely. Thus the crankshaft can be balanced, so it can spin more evenly and the vibrations of the crank to be lost. With weight, This counter causes pressure on the bearings is reduced and evenly distributed.
Crankshaft and connecting rod is to change the translational motion of the piston to move around. These two parts are always suffering from stress and strain are very large. Because it must be made of special materials and the right size. Is at rest and the rotating crankshaft always equilibrium (balance). Hardened bearing surface and should be smooth to reduce wear.
Rotates with the crankshaft is supported by several major bearing fruit. The number of bearings depends on the number of cylinders. Four-cylinder motor has 3 bearings and six-cylinder motor has 4 main bearings. These bearings are made of steel mixed with some babbit or with aluminum. Connecting rod and crankshaft are made from cast iron. Installation of the connecting rod crankshaft bearings coated with wear.