UN R75 Supplement 19 (00 series) · UNECE Regulation No. 75 (ECE R75) — Uniform provisions concerning the approval of pneumatic tyres for L-category vehicles.
UN R75 — Supplement 19 to the 00 series of amendments
Supplement 18 → 19
- What changed
- The tyre markings and the approval mark no longer need to be moulded on, to or into the tyres. They must be clearly legible, indelible and raised above or sunk below the tyre surface.
- Paragraph 6.2.3. no longer applies its ±3.5 per cent outer diameter limit after the load/speed performance test to tyres with radial structure.
- For tyre sizes other than those listed in Annex 5, the tyre-size designation now includes an indication of the structure (paragraph 2.20.3.).
- Why
- The tyre-size designation changes in line with the changes to UN Regulation No. 30 by Supplement 21 to the 02 series of amendments.
- The word “moulded” is a technical limitation linked to the technology available at the time of the first issue of the regulations.
- For radial tyres, the variation of outer diameter measured six hours after the load/speed performance test is far below ±3.5 per cent.
Q1What changed99 changes
Tyre-size designation (paras 2.20. to 2.20.6.)
For tyre sizes listed in Annex 5, the tyre-size designation is the designation shown in the first column of the tables in Annex 5. For other tyre sizes, new paragraphs 2.20.3. to 2.20.3.3. add an indication of the structure: “-” or “D” (diagonal), “B” (bias-belted) or “R” (radial-ply). Paragraph 2.20.4. puts “V” (maximum speeds in excess of 240 km/h but below 270 km/h) or “Z” (270 km/h or above) before the structure. New paragraph 2.20.6. adds the suffix “M/C” for tyres intended to be fitted on rims designed for motorcycles. It is mandatory for a nominal rim diameter equivalent to code 13 (330 mm) or above and optional for tyre sizes listed in Annex 5. Paragraphs 2.19.4. on the prefix “AT”, 3.1.13. on tyre to rim fitment and “M/C”, and 3.1.14. on “V” or “Z” marking are deleted.
Service description (paras 2.39., 3.1.5. to 3.1.5.2.)
New paragraph 2.39. defines “Service description” as the association of the load index with a speed category symbol (for example, 72H). Paragraph 3.1.5. reads “A service description” instead of “An indication of the tyre's speed category symbol”, and paragraph 3.1.6. on the load-capacity index is deleted. Paragraph 3.1.5.1. covers tyres suitable for speeds above 240 km/h but below 270 km/h and identified with the letter code “V” within the size designation. Paragraph 3.1.5.2. covers tyres suitable for speeds above 270 km/h and identified with the letter code “Z” within the size designation. For these tyres, the service description is marked within parenthesis, with the load-capacity index applicable at 210 km/h (“V”) or 240 km/h (“Z”). Before this supplement, these were paragraphs 3.1.15. and 3.1.16.
Markings: structure, moulding and date of manufacture (paras 3.1.4., 3.4. and 3.4.1.)
The indication of the structure in paragraph 3.1.4. is now optional: “BIAS-BELTED” on bias-belted tyres and “RADIAL” on radial-ply tyres. Before this supplement, bias-belted and radial-ply tyres had the letter “B” or “R” in front of the rim-diameter marking, and the words could be added. The text for diagonal (bias-ply) tyres, “no marking, or the letter “D””, is deleted. The markings of paragraph 3.1. and the approval mark of paragraph 5.4. no longer need to be moulded on, to or into the tyres. They must be clearly legible, indelible and raised above or sunk below the tyre surface. If not moulded, the date of manufacture must be applied not later than 24 hours after the tyre is removed from the mould.
Definitions of bias belted, radial and snow tyre (paras 2.5.2., 2.5.3. and 2.33.)
In the “bias belted” definition (paragraph 2.5.2.), the belt now comprises “one or more layers” instead of “two or more layers”. It no longer says “of diagonal (bias-ply) type”. Its ply cords that extend to the beads are laid at alternate angles of substantially less than 90° to the centre line of the tread. Paragraph 2.5.3. now says “Radial” or “radial-ply”, and footnote 1 (“Applicable also to Regulation No. 54”) and its references are deleted. The “snow tyre” definition (paragraph 2.33.) now says “a normal tyre” instead of “an ordinary (road-type) tyre”. It adds “with regard to its ability to initiate or maintain vehicle motion” and deletes the sentence on the tread pattern of a snow tyre.
Load/speed performance test (para. 6.2.3. and Annex 7)
Paragraph 6.2.3. limits the change of outer diameter, measured at least six hours after the load/speed performance test, to ±3.5 per cent. Tyres with radial structure are now exempt from this limit. Annex 7, paragraph 2.6., gives the procedure for a second test to assess the top performances of tyres suitable for speeds above 240 km/h. It now adds the condition “and whose service description is marked in parentheses”. Other changes in Annex 7 and paragraph 6.2.1.1. update or remove paragraph references, renumber paragraph 2.2.5. as 2.2.4. and change “20°°C” to “20 °C”.
Approvals without Supplement 19 until 3 months after entry into force (para. 12.4.)
New paragraph 12.4. covers the period until 3 months after the date of entry into force of Supplement 19. Until then, Contracting Parties applying this Regulation may continue to grant and/or extend type approvals to the original version without taking into account Supplement 19.
Renumbering, references and smaller text changes
Paragraph 2.5.4. becomes 2.6., and paragraphs 2.6. to 2.18. become 2.7. to 2.19. Paragraphs 2.20. to 2.31. become 2.21. to 2.32., and paragraphs 2.33. to 2.37. become 2.34. to 2.38. Paragraphs 3.1.7. to 3.1.12. become 3.1.6. to 3.1.11., and paragraph 3.1.17. becomes 3.1.12. References in paragraphs 2.32.1., 2.37.1., 4.1.14., 4.1.16. and 6.1.2.1. and in Annex 3, paragraph (d), are updated. Paragraphs 4.2. and 5.2. now say “type of tyre”, and paragraph 2.36. says “Motorcycle tyre” and category “O1”. In Annex 2, the approval number is now 002439, and “a = 9 mm (min.)” for the approval mark is deleted.
Q2Why it changed
- Proposed by
- Experts from the European Tyre and Rim Technical Organization
- Working party
- GRBP, 72nd session (September 2020)
Reasons
The proposal changes the definition of the tyre-size designation to include prefixes and suffixes and the code for the tyre structure. This is in line with the changes to UN Regulation No. 30 by Supplement 21 to the 02 series of amendments. The first paragraph of the definition also clarifies that the definition is only valid for sizes not listed in Annex 5.
Sources (3)
“it is proposed to change the definition of the tyre size designation by including prefixes and suffixes as well as the code for the tyre structure”
“In line with the changes introduced in UN Regulation No. 30 by Supplement 21 to the 02 series of amendments”
“it is proposed to clarify in the initial paragraph of the section that the following definition is only valid for sizes that are not listed in Annex 5”
The old wording on the “M/C” marking in paragraph 3.1.13. implied that mounting motorcycle tyres on motorcycle rims is not the standard configuration. The proposed wording is aimed to clarify that this is the standard configuration and that “M/C” marking is optional for sizes listed in Annex 5. “M/C” is part of the tyre-size designation, which is a mandatory marking.
Sources (3)
“Wording regarding "M/C" marking in current paragraph 3.1.13. implies that mounting motorcycle tyres on motorcycle rims does not represent the standard configuration.”
“Proposed wording is aimed to clarify that mounting motorcycle tyres on motorcycle rims is the standard configuration and that "M/C" marking is optional for the sizes listed in Annex 5.”
“"M/C" is part of tyre size designation, which is a mandatory marking.”
The word “moulded” is a technical limitation linked to the technology available at the time of the first issue of the regulations. Moulding is now only one of the various technical solutions. The removal of this limitation would be advisable, following the principle of not stopping technical innovations. ETRTO proposes to allow tyre marking methods other than moulding. The criteria are clearly legible and indelible markings, and marking of the manufacturing date within 24 hours after de-moulding.
Sources (5)
“the use of wording “moulded” is a technical limitation linked to the technology available at the time of the first issue of the regulations, but now is only one of the various technical solution.”
“The removal of this technical limitation would be advisable following the principle of not stopping the technical innovations.”
“ETRTO proposes to amend the UN regulations on tyres in order to allow tyre marking methods other than moulding by keeping the following criteria:”
“Any technical solution alternative to the "moulding" shall guarantee that the markings on the tyre sidewall is clearly legible and indelible.”
“It shall be made sure that the marking of the manufacturing date will be done within 24 hours after de-moulding of the tyre”
For radial tyres, the variation of outer diameter measured six hours after the load/speed performance test is far below ±3.5 per cent.
Source
“For radial the variation of outer diameter of the tyre, measured six hours after the load/speed performance test as specified in paragraph 2 of Annex 7, is far below ±3.5 per cent”
The “bias-belted” definition changes to converge to consistent definitions across UN tyre Regulations. The “snow tyre” definition replaces “ordinary (road-type) tyres”, which is not defined, with “normal tyre”. It removes the note that snow tyres generally have more widely spaced ribs or blocks, to avoid impeding technical progress. Its wording is adapted to that used in the other tyre UN Regulations.
Sources (3)
“The purpose of this change is to converge to consistent definitions across UN tyre Regulations”
“It is proposed to amend the definition of "snow tyres" by replacing "ordinary (road-type) tyres" (which is not defined) by "normal tyre"”
“removing the note that snow tyres generally have more widely spaced ribs or blocks (to avoid impeding technical progress) and adapt the wording to that used in the other tyre UN Regulations”
Document trail
- 2020-06ProposalECE/TRANS/WP.29/GRBP/2020/14Proposal by the experts from the European Tyre and Rim Technical Organization
- —Amended in sessionGRBP-72-28Amendments to the proposal by the experts from ETRTO
- —Working party adoptsECE/TRANS/WP.29/GRBP/70Session report, para. 14
- 2020-12Sent to WP.29ECE/TRANS/WP.29/2021/6Text that GRBP sent to WP.29 and AC.1
- 2021-03WP.29 adoptsECE/TRANS/WP.29/1157Adopted at the 183rd session (session report, para. 137)
- 2021-09-30In forceC.N.326.2021.TREATIES-XI.B.16.75UN depositary notification
Q3Who is affected
Vehicle manufacturer
- No direct action for this role.
Component supplier
- If not moulded, apply the date of manufacture within 24 hours after the tyre is removed from the mould.
- Make sure that markings are clearly legible, indelible and raised above or sunk below the tyre surface (paragraph 3.4.).
Technical service / Approval authority
- Do not apply the ±3.5 per cent outer diameter limit after the load/speed performance test to tyres with radial structure.
- Check that markings are clearly legible, indelible and raised above or sunk below the tyre surface (paragraph 3.4.).
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ⓘ This report gives advice only. It is not legal or type-approval advice.