Description
This part of SANS 1550 specifies the general requirements for motor vehicle pneumatic tyres,
giving the basic definitions, details of the parameters used for tyre marking requirements and a test
method for the measurement of tyre dimensions.
Contents Page
1 Scope………………………………………………………………………………………………………………………………………………..1
2 Normative references…………………………………………………………………………………………………………………….1
3 Definitions……………………………………………………………………………………………………………………………………….1
4 General Requirements……………………………………………………………………………………………………………….3
4.1 Tyre size designation ……………………………………………………………………………………………………………….3
4.2 Nominal section ………………………………………………………………………………………………………………………4
4.3 Nominal rim diameter ……………………………………………………………….….……….……………………..4
4.4 Nominal aspect ratio……………………..…….………………….……………….…………………………………….5
4.5 Speed rating symbol markings…… …………………………………………….………………………………….5
4.6 Load index number…………………………………….………… …………………………….…………………………5
4.7 Regrooving……………….……………………….………………………………..…………….……………………………5
5 Inspection and Test ……..…………………………………………………………………………………………………6
5.1 Visual inspection …………………………………..………………………………………………………………………8
5.2 Measuring the section width and overall diameter ………………………………………..…………..9

