Post by Deleted on Mar 30, 2018 17:41:37 GMT 1
I must confess I do not test class VII so have no practical experience when it comes to understanding the following;
I own a class VII Transit, last year I bought 4 tyres 215/75R 16C. The tyres are marked with 113/111R 8 PR, reading the testers manual I understand their meaning and how to read the load index table, but what I don't understand is this part at the bottom of the information advising how to use single tyres in dual formation, so here goes;
I look up the load index from the tyre wall and compare to the table of data, I have;
113 = Single 2300 Kg and Dual 4600 Kg, and
111 = Single tyres used in dual format, so
111 = Dual format 4600 Kg.
If I use the second load index table and use the tyre size and 8 PR, I can still work out the above no problems, and I understand all the above, so here is my problem;
The testers manual says;
I own a class VII Transit, last year I bought 4 tyres 215/75R 16C. The tyres are marked with 113/111R 8 PR, reading the testers manual I understand their meaning and how to read the load index table, but what I don't understand is this part at the bottom of the information advising how to use single tyres in dual formation, so here goes;
I look up the load index from the tyre wall and compare to the table of data, I have;
113 = Single 2300 Kg and Dual 4600 Kg, and
111 = Single tyres used in dual format, so
111 = Dual format 4600 Kg.
If I use the second load index table and use the tyre size and 8 PR, I can still work out the above no problems, and I understand all the above, so here is my problem;
The testers manual says;
Maximum load in dual formation = Maximum load in single formation x 1.91
Reading the equation one would think that is straight forwards, but I see it as a problem because DVSA are saying "Equal" and I can't see equal!
First lets go back to the DVSA load index table, it says;
113 = Single 2300 Kg and Dual 4600 Kg maximum weights
Taking the right hand side of the equation;
2300 Kg x 1.91 = 4393 Kg
This I am assuming is the maximum load of the tyres in dual format regarding the above equation!
If then I take it that the maximum load these tyres can take is 4393 Kg, then the maximum axle load being 4600 Kg, what is this information saying?
If I look at the load on the tyre wall which says 1150 Kg, then times that by two and you get 2300 Kg, which matches the table of data, however when the tyres are dual marked with two load indexes, then the lesser load index of 1090 Kg in dual format x 4 = 4360 Kg
How is a tester supposed to interpret these results in comparison to the load index tables?
First lets go back to the DVSA load index table, it says;
113 = Single 2300 Kg and Dual 4600 Kg maximum weights
Taking the right hand side of the equation;
2300 Kg x 1.91 = 4393 Kg
This I am assuming is the maximum load of the tyres in dual format regarding the above equation!
If then I take it that the maximum load these tyres can take is 4393 Kg, then the maximum axle load being 4600 Kg, what is this information saying?
If I look at the load on the tyre wall which says 1150 Kg, then times that by two and you get 2300 Kg, which matches the table of data, however when the tyres are dual marked with two load indexes, then the lesser load index of 1090 Kg in dual format x 4 = 4360 Kg
How is a tester supposed to interpret these results in comparison to the load index tables?