Frequently Asked Questions

The Chain Doctor

16. How do you measure chain width?
There are a number of common terms that are used to describe silent chain width:

Width over heads - This is the maximum chain width and is measured across the “headed” or “riveted” pins.
Width over links - This is the measurement across link plates only, excluding pin heads or any washers that are on the ends of pins.
Width between guides - This is the measurement between guide plates and is used only with side guide chain.
Nominal width - This is not a measurement. It is a general approximation of chain size used in part numbering and catalogues.