Basically no tyre will ever be perfectly round.
Have you seen the yellow, red
& white dots on the sidewalls of some tyres?
These dots indicate various things like stiffest part of the sidewall
(White), lightest part
(Yokohama Yellow) of the tyre and highest part of sidewall
(Yokohama Red).
Different manufacturers use different colours though.
Not all tyres will have all the marks and those that do usual only have the Lightest and highest marks
(Yellow
& Red).
The yellow dot is meant to line up with the valve.
The red dot
(if there is one, should take precedence though and should line up with the lowest part of the rim of the alloy
(usually marked with a dimple.
Naturally balancing can help sort out the imperfections so it's not really that important for the yellow dot to line up with the valve.
Then there are the coloured stripes that run the circumference of the tyres
(in the tyre tread).
These are run-off stripes which prevent the car from pulling to one side.
The lightest stripe should be on the outer part of each wheel.
If both stripes are biased to the right, the car will have a tendancy to pull to the right.
It's not necessary to adjust the tracking as the tyres will wear to comensate for the run-off.
It can also be difficult for directional tyres to be fitted with correct run-off as the suppliers can deliver un-matched sets.
The pulling to one side will only be short term until the tyre
"beds in"
If a car is left standing for long periods, the tyre can egg.
Also locking up will cause flatspots.
Either of which balancing will not sort.
And then as mentioned above, Chinese fakes can also show bigger in-perfections.
