Originally Posted by Mr_D
Always makes me wonder why someone would do anything but what a manufacturer says! The companies spend LOTS of money running non and fully destructive testing that not many others are qualified to do. Then along comes joe blow saying they're wrong, just doesn't make sense!
Retired transportation engr here.
then why does one tire assosiation uses an other system then the other ( ETRTO versus TRA)?
After 2005 TRA swiched over to the calculation of ETRTO, but only for Standard load and Extraload/XL/Reinforced , but for C-load/6ply and up TRA still uses the power of 0,7, while ETRTO has used since decades 0,8 power for all kind of tires.
Michelin , as I described in my last post, calculates diffferent for the American market, though the tires are in fact the same. Michelin even uses in Europe the 0,9 power , wich is acording to an American IR J.C.Daws the way it should be calculated for larger tires with high maxloadpressure . If Michelin thougt that Mr Daws was wrong , they would not use his calculation.
Figalegro has weighed once , and if He can procuce , 1: the advice pressures on the RV, 2: the advice-pressures he determined looking back the loads he weighed, in the pressure/loadcapacitylist he had.
If he then can give 4point weighing, he can use my spreadsheet part 3 , where you can give the 4 point weighing.
I am shure my advice then will be higher then 2: and probably higher then 1:.
So never wrong for the savety of the tires.
But how has Figalegro weighed, was it loaded as he uses on vacation? ( so with persons and all the load in it)
You can use a good calculation, but if the input is wrong , it still can give dangerous situations.