Motorcycle chains may need to be replaced after extensive use. It is important you purchase the correct replacement chain. Regardless of a chain's length--which you can adjust easily--the pitch and width of the chain must be accurate. Motorcycle chains come in standard pitch sizes of 5/8 inch or ½ inch. The standard widths of motorcycle chains are 3/16 inch, 5/16 inch, 1/8 inch, 3/8 inch and 1/4 inch. When measuring, be sure you are measuring the width and pitch correctly within those size guidelines.
Position the chain to lay flat and straight. Measure the length of the chain from end to end.
Measure the pitch between the roller pins. The pitch is simply the distance between each roller pin. Measure the distance between the centre of one roller pin to another. If yours is a standard motorcycle chain, you should have a pitch measurement of 5/8 inch or ½ inch.
Measure the chain's width. The width is the distance between two inner roller plates (the alternating flat parts of an individual link that are on the inside of the chain). If you have a standard motorcycle chains, your measurement should be 3/16 inch, 5/16 inch, 1/8 inch, 3/8 inch or 1/4 inch.
If you are buying a new chain, its length can be a little longer. You can always remove a link or links if the chain needs to be shortened.