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Basic Tyre Knowledge

Air Pressure, Load Index

Points to note when fitting Extra Load (XL) /Reinforced (RF) tires

What are Extra Load (XL) / Reinforced (RF) tires?

ETRTO reinforced tires are set with higher air pressure and load capacity than ETRTO standard tires. Air pressure for ETRTO standard tires is set at 250kPa when at maximum load capacity,whereas it is set at 290kPa for ETRTO reinforced tires. The higher air pressure enables a heavier load. It is necessary to increase the volume inside the tire in order to support heavier vehicles. However, with ETRTO reinforced tires, the load index is large, making it possible to support a heavier vehicle even when the tires are the same size increasing air pressure. It is necessary to fill up the tires to the appropriate air pressure when fitting reinforced tires (extra load tires).

  • Points to note due to differences in standard for tires of identical size

The load index differs between JATMA standard and ETRTO reinforced tires even when the size is the same, which means the suitable air pressure also differs. In case you fit tires of differing standards, it is necessary to fill the tires to a suitable pressure in accordance with the particular standard.

  • Make sure reinforced tires have the correct air pressure!

The Load Index (LI) differs between JATMA standard and ETRTO reinforced tires even when the size is the same. It is important to ensure the correct air pressure when inching-up to reinforced tires (extra load tires).

Be sure that the Load Index (LI) of the tire is not lower than the original equipment tire. *Excludes exceptions