Group ND Proposal
Treaded tyres must be used with the pattern extending both around and across the tyre. Single and 2 groove "slicks" are not considered as “treaded”
Tyres listed on the MSA "GROUPS N & S – APPROVED TYRE LIST " are acceptable, but others not listed, may also meet the requirements above.
Tyre width must be in accordance with the Australian Tyre and Rim handbook for the wheel width being used
Justification and Rationale
Expanding the tyre choice and not proscribing 60% aspect ratio will enable more suitable tyres to be chosen when a competitor wishes to increase the rim diameter as per other rules/freedoms.