What is a bolt pattern (PCD)?
Reading bolt patterns and checking wheel compatibility.
PCD is the diameter of the circle passing through the centres of the wheel mounting holes. 5×112 means five holes on a 112 mm pitch circle.
Reading the notation
- 4×100: four holes, 100 mm pitch circle.
- 5×120: five holes, 120 mm pitch circle.
- 6×139.7: six holes, 139.7 mm pitch circle.
Checking the PCD
With four or six equally spaced holes, measure between the centres of opposite holes. Five holes have no opposite pair: use a bolt-pattern gauge or manufacturer specifications. Measuring to the edge of a hole depends on the hole diameter and does not give the exact PCD.
Compatibility
The wheel PCD must match the hub. Matching PCD alone does not guarantee fitment: also check centre bore, offset, width, fasteners, load rating and brake clearance.