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Wheels. V17 outcome 4 pt 3. Did You Know?. The earliest record of the wheel being used is in Mesopotamia (Iraq) around 3500 BC as a potters wheel. The first vehicle recorded was a Mesopotamian chariot in 3200 BC and the first spoked wheel in Egypt around 2000 BC.
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Wheels V17 outcome 4 pt 3
Did You Know?..... • The earliest record of the wheel being used is in Mesopotamia (Iraq) around 3500 BC as a potters wheel. • The first vehicle recorded was a Mesopotamian chariot in 3200 BC and the first spoked wheel in Egypt around 2000 BC. • The wheel was developed independently in Europe in 1400 BC. (without Middle Eastern influence) • The Aztecs however reached great levels of sophistication without inventing it. In fact no western hemisphere civilization developed the wheel before contact with Europe.
Wheels n tyres • Like tyres, wheels come in all shapes and sizes. • Get it right and the result can be better style and superb handling • Get it wrong and you can have a stylish heap of un-drivable scrap.
First things first • It may seem obvious, but count the holes.
Then check the PCD (Pitch Circle Diameter) Formula to work out 5 stud PCDs Just because you get the right number of holes doesn’t mean they are the same position as replacement wheels Measure from inside edge of 1 hole to the outside edge of the next and refer to chart
Centre Spigot Diameter • The studs do not hold the weight of the car. That is the job of the central spigot and therefore if the new one is too big the weight will be held by the studs. Use a spigot locating ring, as aftermarket rims are usually larger than the originals.
Einpresstiefe • OK, offset, inset or outset. This is the way the rim sits on the car, does it stick out, set in or neither. • This is the vital difference that could make the vehicle un-drivable.
Tyre bead profiles / rim contour designations • J, JJ, K, JK, B, P and D relate to the shape of the rim that holds the tyre in place.
14” Rim diameter Hump profile index 6J = 6” deep + bead shape code J Wheel offset in millimetres