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Jellybelly's Guide to the world of wheels & tyres !!!

So……. being the simple soul I am, I have no cravings for wheels other than standard, maybe it's my age !
But I do however realise that a lot of people love or are even obsessive about the world of wheels.
I thought it was time I did a bit of reading to figure this out. So for the folk who don't understand then this is my guide that may help you as it has helped me as I've researched it.


What are the meanings briefly:
All the items below are often stamped on wheels, the guide will show how to measure them and also what they mean if the info is not stamped on the wheel.

The stamps on the wheel can look like this 5J x 13 ET45

5J refers to the RIM WIDTH, J  also refers to the type of bead…. 13 is the Wheel Diameter…. ET45 is the Offset or ET

Wheel Diameter = This is the outside diameter of the wheel itself so 13", 14", 15" etc

Pitch Circle Diameter or PCD = This is the area where the wheel bolts to the hub, Mk1 Golf standard fitment is 4 x 100mm

Offset or ET =  This is the measurement  that the mounting face is from the Centre line of the Rim Width

Wheel Hub Centre Bore = This is the centre of the wheel that locates over the hub 57.1mm

Adaptors = Convert you standard PCD to a new PCD to match your wheels also acting as a Spacer

Spacers = These are use to change the ET of your wheels to widen the track or the move the wheel away from the strut

Spigot Ring = These are used to reduce a larger Centre Bore fitment to you original Centre Bore fitment

Wobble Bolts = These have an offset head that allows them to adjust to a small difference in PCD.


Now the brief bit is over it's time to get down and dirty with it: Wheel Diameter

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