Tires: Tyre, level surfaces, robin robin

Question
sir,
    why the Maximum load(indicated in side wall of tyre) is less for duel fitment than single fitment.

regards,
robin.

Answer
Robin,

There are 2 reasons for that.

1)  The production of anything involves some variation.  This is true for tires as well.  There is some bit of variation in the diameter of tires - even virtually identical tires.  That results in a difference between the loads each tire is carrying.

For example, if I were to take 2 tires and clamp them together - and the 2 tires were a different size (so there a difference in diameter).  If I then gradually load the tires up, the tire with the larger diameter will be carrying 100% of the load until the tire with the smaller diameter touches the ground.  And this continues throughout the loading process.  The larger tire will always carry more of the load.

2)  Unfortunately vehicles don't always drive on level surfaces.  If a vehicle drives on an uneven surface, it is possible for the surface to load one side of the paired duals more than the other.  

For those 2 reasons, the maximum load for a  dualled tire is reduced compared to the single.