BRITISH STANDARD AUTOMOBILE SERIES BS AU 50 1 6 1c 2002 ISO 5751 1 2001 Tyres and wheels — Part 1 Tyres — Section 6 Motorcycle tyres — Subsection 6 1c Specification of general requirements and design[.]
BRITISH S TAND ARD AUTO MO BILE S E RIE S BS AU -1 c: 0 ISO 75 -1 :2 0 Tyres and wheels — Part : Tyres — S ection 6: Motorcycle tyre s — Subsection c: Specification of general requirements and design guide for designations, dimensions and load ratings for metric series tyres I C S 83 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW BS AU 50-1 6.1 c:2002 National foreword This B ritis h S tandard rep roduces verb atim IS O 751 - : 00 and implements it as the UK national s tandard It s up ersedes BS AU - b : 95 which is withdrawn The UK p articip ation in its p rep aration was entrus ted to Technical C o mmittee AUE /4 , Tyres and wheels for motor vehicles , which has the resp onsib ility to: — — aid enquirers to unders tand the text; p res ent to the res pons ib le international/E urop ean comm ittee any enquiries on the interp retation, or p rop osals for change, and keep the UK interests informe d; — monitor re lated international and E urop ean develop ments and p rom ulgate them in the UK A list of organiz ations rep resented on this committee can b e ob tained on reques t to its s ecretary C ross-references The Britis h S tandards which imp lem ent international or E urop ean p ub lications refe rred to in this document may b e found in the BS I S tandards C atalogue under the s ection entitled “International S tandards C orresp ondence Index”, or b y using the “Find” facility of the BS I S tandards E lectronic C atalogue A Britis h Standard does not p urport to include all the necess ary p rovisions of a contract Us ers of British S tandards are resp onsib le for their correct ap p lication Compliance with a British Standard does not of itself confer immunity from legal obligations Summary of pages This document comp ris es a front cover, an inside front cover, the IS O title p age, p ages ii to iv, pages to 4, an ins ide b ack cover and a b ack cover This Britis h S tandard, having b ee n p rep ared under the The BS I cop yright date dis p layed in this document indicates when the document was las t iss ued direc tion of the E nginee ring S ector P olicy and S trategy C o mmittee, was p ub lis he d under the authority of the Amendments issued since publication S tandards Polic y and S trategy C o mmittee on March 00 Amd No © BS I March 002 ISBN 80 391 D ate C omments BS AU 50−1.6.1c:2002 I SO I N TE RN ATI ON AL S TAN D ARD 5751 -1 Fi fth ed i ti on 2001 -1 2-1 M otorcycl e tyres an d ri m s (m etri c seri es) — Part : Desi g n g u i d es Pneumatiques et jantes pour motocycles (séries millimétriques) — Partie 1: Guide de conception Reference nu m ber I SO 5751 -1 : 2001 (E) BS AU 50−1.6.1c:2002 ii BS IAU 50−1.6.1c:2002 SO 5751 -1 : 2001 (E) Con ten ts Pag e Foreword i v Scope N orm ati ve referen ces Term s an d d efi n i ti on s Tyre desi g n ati on Tyre d i m en si on s Tread fi g u rati on s 7 Tyre l oad -carryi n g capaci ty 8 Speed sym bol s Cen tri fu g al rad i u s 1 An n ex A (i n form ati ve) G u i d el i n e val u es for m etri c seri es Bi bl i og raph y iii BS AU 50−1.6.1c:2002 I SO 5751 -1 : 2001 (E) Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies) The work of preparing International Standards is normally carried out through ISO technical committees Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part The main task of technical committees is to prepare International Standards Draft International Standards adopted by the technical committees are circulated to the member bodies for voting Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote Attention is drawn to the possibility that some of the elements of this part of ISO 5751 may be the subject of patent rights ISO shall not be held responsible for identifying any or all such patent rights ISO 5751 -1 was prepared by Technical Committee ISO/TC 31 , Tyres, rims and valves, Subcommittee SC 0, Cycle, moped, motorcycle tyres and rims This fifth edition cancels and replaces the fourth edition (ISO 5751 -1 :1 994), which has been technically revised ISO 5751 consists of the following parts, under the general title Motorcycle tyres and rims (metric series) : Part : Design guides Part 2: Tyre dimensions and load-carrying capacities Part 3: Range of approved rim contours Annex A of this part of ISO 5751 is for information only iv BS AU 50−1.6.1c:2002 I N TEN RATI ON ALTS AN D A DR I S-1 575 O1 : (1 002)E M otorcycl e tyres an d ri m s (m etri c seri es) — Part : Desi g n g u i d es Scope Th i s part of I SO 5751 g i ves g u i d el i n es for th e d esi g n an d speci fi es th e d esi g n ati on , th e cal cu l ati on of d i m en si on s an d th e l oad -carryi n g capaci ty of m etri c-seri es m otorcycl e tyres Th i s part of I SO 5751 i s appl i cabl e to m otorcycl e tyres wi th a red u ced h ei g h t/wi d th rati o (1 00 an d l ower) th at can be fi tted on cyl i n d ri cal bead seat ri m s or 5° tapered bead seat ri m s I t i s al so appl i cabl e to oth er cepts of tyre an d ri m , i n wh i ch case, h owever, th e appropri ate ri m /secti on rati os an d coeffi ci en ts wi l l h ave to be establ i sh ed N OTE See I SO 4249 for requ i rem en ts coveri n g m otorcycl e tyres an d rim s (cod e-d esi gn ated seri es) of ri m d iam eter cod e and above, and I SO 6054 for th ose of cod e an d bel ow N orm ati ve referen ces Th e fol l owi n g n orm ati ve d ocu m en ts tai n provi si on s wh i ch , th rou g h referen ce i n th i s text, sti tu te provi si on s of th i s part of I SO 5751 For d ated referen ces, su bseq u en t am en d m en ts to, or revi si on s of, an y of th ese pu bl i cati on s d o n ot appl y H owever, parti es to ag reem en ts based on th i s part of I SO 5751 are en cou rag ed to i n vesti g ate th e possi bi l i ty of appl yi n g th e m ost recen t ed i ti on s of th e n orm ati ve d ocu m en ts i n d i cated bel ow For u n d ated referen ces, th e l atest ed i ti on of th e n orm ati ve d ocu m en t referred to appl i es M em bers of I SO an d I EC m n tai n reg i sters of cu rren tl y val i d I n tern ati on al Stan d ard s I SO 4000-2, Passenger car tyres and rims — Part 2: Rims I SO 42 23-1 , Definitions of some terms used in the tyre industry — Part 1: Pneumatic tyres I SO 42 51 -3, Tyres (ply rating marked series) and rims for agricultural tractors and machines — Part 3: Rims Term s an d defi n i ti ons For th e pu rposes of th i s part of I SO 5751 , th e term s an d d efi n i ti on s g i ven i n I SO 4223-1 appl y 4 Tyre d esi g n ati on G en eral Th e d esi g n ati on of th e tyre sh al l be sh own on i ts si d ewal l an d sh al l i n cl u d e th e fol l owi n g m arki n g s, pl aced cl ose to each oth er: si ze an d stru cti on (see 2); servi ce d escri pti on (see 3) I ©S O – 002 Al l irth gs ersed evr 1 BS AU 50−1.6.1c:2002 I S-1 575 O1 : (1 002)E Si ze an d stru cti on Ch aracteri sti cs Th e si ze an d stru cti on ch aracteri sti cs sh al l be i n d i cated as fol l ows: N om i n al secti on wi d th 2 § N om i n al Tyre N om i n al aspect stru ction ri m d i ameter rati o cod e cod e N om i n al secti on wi d th Th e n om i n al secti on wi d th sh al l be expressed i n m i l l i m etres N om i n al aspect rati o Th e n om i n al aspect rati o sh al l be expressed as a percen tag e I t sh al l be a m u l ti pl e of for aspect rati os 70 an d h i g h er, an d a m u l ti pl e of for aspect rati os l ower th an 70 4 Tyre stru cti on cod e Th e tyre stru cti on cod e sh al l be “B” for bi as bel ted type stru cti on s, “-” for d i ag on al pl y tyres, an d “R” for rad i al pl y tyres N OTE See al so 4 Oth er cod es wil l be establ i sh ed for n ew cepts (construction s) of tyres N OTE Th e term “bi as bel ted structi on ” d escri bes a pn eu m ati c tyre stru ctu re of d i ag on al (bi as pl y) type i n wh i ch the carcass is restricted by a su bstan tial l y i nexten si bl e ci rcu m feren ti al bel t N OTE With referen ce to th e d efi ni ti on of rad ial pl y tyre g i ven i n I SO 4223-1 , for th e pu rposes of thi s part of I SO 5751 , “su bstan ti al l y at 90° ” m eans an g l es between 70° an d 90° as m easu red from the cen trel i n e of th e tread N om i n al ri m d i am eter Th e n om i n al ri m d i am eter sh al l n orm al l y be expressed by a cod e (see Tabl e ) H owever, i t sh al l be expres sed i n m i l l i m etres for n ew an d fu tu re cepts wh ere th e appl i cati on ei th er of exi sti n g tyres on n ew-con cept ri m s or of n ew-con cept tyres on exi sti n g ri m s wou l d be i n com pati bl e Servi ce d escri pti on Th e ch aracteri sti cs sh al l be i n d i cated as fol l ows: Load i nd ex Speed s ym bol Th e l oad i n d ex i s a n u m eri cal cod e associ ated wi th th e m axim u m l oad a tyre can carry at th e speed i n d i cated by i ts speed s ym bol u n d er th e d i ti on s speci fi ed i n cl au se (see Tabl e 3) Th e speed s ym bol i n d i cates th e speed categ ory i n wh i ch th e tyre can carry th e l oad correspon d i n g to i ts l oad i n d ex u n d er th e servi ce d i ti on s speci fi ed i n cl au se (see Tabl e 4) 2 © I SO 002 – Al l ir th g ser sed evr BS IAU 50−1.6.1c:2002 S-1 575 O1 : (1 002)E Tabl e — N om i n al ri m d i am eter an d ri m wi d th cod es Di m ensi on s i n m i l l i m etres N om i n al rim d i am eter cod e Cod e 4 N om i n al rim d i am eter D Ri m wi d th code Cod e M easu ri n g ri m wid th R r m 203 50 38 10 254 60 40, 12 305 85 47 M/C 330 55 M/C 356 50 63, 5 M/C 381 75 70 M/C 406 00 76 M/C 432 50 89 M/C 457 75 95 M/C 483 00 01 , 20 M/C 508 50 1 4, 21 M/C 533 00 27 23 M/C 584 50 39, 00 52, 25 59 50 65 00 78 Oth er servi ce ch aracteri sti cs 4 I n th e case of tu bel ess tyres, th e m arki n g “TU BELESS ” sh al l be sh own on th e tyre 4 I n th e case of a preferred d i recti on of rotati on of th e tyre, an arrow sh al l be u sed to i n d i cate th at d i recti on 4 Tyres d esi g n ed for veh i cl es h avi n g a m axim u m speed capaci ty i n excess of 240 km /h sh al l be i d en ti fi ed by m ean s of th e cod e l etters “VB” or “ZB” for bi as-bel ted stru cti on , “VR” or “ZR” for rad i al stru cti on , wh ere “ZB” an d “ZR” sh ou l d be u sed for n ewl y d esi g n ed m otorcycl es wi th a m axi m u m speed over 40 km /h Th i s i d en ti fi cati on sh al l be pl aced i n si d e th e tyre d es i g n ati on (see 2) i n stead of i n th e tyre stru cti on cod e For speed categ ory “V”, “VB” or “VR” tyres su i tabl e for speed s of over 240 km /h , a servi ce d escri pti on wi th th e speed s ym bol “V” sh al l be m arked i n paren th eses EXAM PLE 1 20/60 VR (55 V) For speed categ ory “ZB” or “ZR” tyres su i tabl e for speed s u p to 70 km /h , a servi ce d escri pti on wi th th e speed s ym bol “W” sh al l be m arked EXAM PLE 20/60 ZR 55 W I ©S O – 002 Al l irth gs ersed evr 3 BS AU 50−1.6.1c:2002 I S-1 575 O1 : (1 002)E I f th e sam e tyres are su i tabl e for speed s of over 270 km /h , th e servi ce d escri pti on sh al l be m arked i n paren th eses EXAM PLE 4 20/60 ZR (55 W) For n om i n al ri m d i am eter cod es an d above, th e su ffi x “M /C” sh al l be ad d ed to th e si ze an d stru cti on m arki n g , to preven t fu si on an d m i sfi tti n g of m otorcycl e tyres on ri m s h avi n g th e sam e n om i n al d i am eters bu t d esi g n ed pri m ari l y for passen g er car tyres i n accord an ce wi th I SO 4000-2 or ag ri cu l tu ral tyres i n accord an ce wi th I SO 42 51 -3 4 Th e m axim um speed approved b y th e tyre m an u factu rer m ay be m arked on th e tyre E XAM PLE “V250” to i d en ti fy a m axi m u m speed of 250 km /h 4 Th e sym bol “M ST” m ay be u sed to i d en ti fy speci al servi ce tyres 4 Th e sym bol “DP” m ay be u sed to i d en ti fy tread type C tyres Exampl es a) a si ze an d stru cti on of b) A m otorcycl e tyre h avi n g n om i n al secti on wi d th , 20 m m , n om i n al aspect rati o, 80, d i ag on al stru cti on , an d n om i n al ri m d i am eter cod e 8, wi th a servi ce d escri pti on si sti n g of a l oad -carryi n g capaci ty of 290 kg , correspon d i n g to l oad i n d ex “65”, an d a m axim um speed of 80 km /h , correspon d i n g to speed sym bol “S”, sh al l be m arked : a) a si ze an d stru cti on of b) n om i n al secti on wi d th , 40 m m , n om i n al aspect rati o, 70, rad i al stru cti on , an d n om i n al ri m d i am eter cod e 7, wi th a servi ce d escri pti on si sti n g of A m otorcycl e tyre h avi n g a referen ce speed i n exces s of 240 km /h (cod e l etter “ZR”), a referen ce l oad -carryi n g capaci ty of 300 kg , correspon d i n g to l oad i n d ex “66”, an d © I SO 002 – Al l ir th g ser sed evr BS IAU 50−1.6.1c:2002 S-1 575 O1 : (1 002)E a m axim um speed of 270 km /h , correspon d i n g to speed sym bol “W”, sh al l be m arked : I n th e case of “VR” an d “VB” tyres approved for speed s i n excess of 240 km /h or “ZR” an d “ZB” tyres approved for speed s i n excess of 270 km /h , th e servi ce d escri pti on sh al l be m arked i n paren th eses EXAM PLE 1 40/70 ZR M/C (66 W) Th e actu al m axi m um speed certi fi ed by th e tyre m an u factu rer m ay be m arked on th e tyre E XAM PLE “V280” to i d en ti fy a m axi m um speed of 280 km /h Tyre d i m en si on s Cal cu l ati on of d esi g n tyre d i men si on s R Th eoreti cal ri m wi d th , Th e th eoreti cal ri m wi d th , R th = KS R th th , sh al l be cal cu l ated as fol l ows: N wh ere K i s th e ri m /secti on rati o; S i s th e n om i n al secti on wi d th N For tyres of exi sti n g cepts, sh al l be eq u al to 0, for aspect rati os 70, 65, 60, an d 0, for aspect rati os 55, 50 K wi l l be d efi n ed l ater for aspect rati os bel ow 50 M easu ri n g ri m wi d th , R Th e m easu ri n g ri m wi d th , 0, for aspect rati os 00, 90, 80, N OTE K m R m , i s th e wi d th of th e exi sti n g ri m n earest to Desi g n tyre secti on wi d th , Th e d esi g n tyre secti on wi d th , S, R th See Tabl e for wi d th s of exi sti n g ri m s S sh al l be th e n om i n al secti on wi d th , S N , tran sferred from R th to R m , cal cu l ated as fol l ows: S=S N + K (R m - R th ) rou n d ed to th e n earest wh ol e n u m ber I ©S O – 002 Al l irth gs ersed evr 5 BS AU 50−1.6.1c:2002 I S-1 575 O1 : (1 002)E For tyres of exi sti n g cepts, K = 0, Desi g n tyre secti on h ei g h t, Th e d esi g n tyre secti on h ei g h t, H=S H N H H, sh al l be cal cu l ated as fol l ows: S 00 rou n d ed to th e n earest wh ol e n u m ber, wh ere S i s th e n om i n al secti on wi d th ; N HS / i s th e n om i n al aspect rati o Desi g n tyre overal l d i am eter, Th e d esi g n tyre overal l d i am eter, D o = D r D o D o , sh al l be cal cu l ated as fol l ows: + 2H wh ere D i s th e n om i n al ri m d i am eter; r H i s th e d esi g n tyre secti on h ei g h t For th ose tyres u si n g a n om i n al ri m d i am eter cod e, see Tabl e for th e val u e of D r to be u sed Val u es G u i d el i n e val u es for th e d esi g n tyre d i m en si on s for m etri c-seri es m otorcycl es are g i ven i n an n ex A M axi m u m overal l tyre d i m en si on s i n servi ce G en eral Th e cal cu l ati on s of 2 an d are for u se b y veh i cl e m an u factu rers i n d esi g n i n g for tyre cl earan ces M ax overal l wi d th i n servi ce, W Th e m axim um overal l wi d th i n servi ce, W 2 W m ax = m ax , sh al l be cal cu l ated as fol l ows: m ax Sa wh ere S i s th e d esi g n tyre secti on wi d th ; a i s th e appropri ate coeffi ci en t (see Tabl e 2) I t i n cl u d es protecti ve ri bs, l etteri n g , em bel l i sh m en ts, tread overh an g , m an u factu ri n g tol eran ces an d g rowth d u e to servi ce 6 © I SO 002 – Al l ir th g ser sed evr BS IAU 50−1.6.1c:2002 S-1 575 O1 : (1 002)E M ax overal l d i ameter i n servi ce, D Th e m axim u m overal l d i am eter i n servi ce, D D o, m ax = D r + o, m ax , sh al l be cal cu l ated as fol l ows: o, m ax Hb wh ere D i s th e n om i n al ri m d i am eter; r H i s th e d esi g n tyre secti on h ei g h t; b i s th e appropri ate coeffi ci en t (see Tabl e 2) I t i n cl u d es m an u factu ri n g tol eran ces, g rowth d u e to servi ce, an d d eform ati on d u e to cen tri fu g al force M i ni mum di men si on s — Secti on wi d th, Th e m i n i m um secti on wi d th , S , S sh al l be eq u al to th e prod u ct of th e d esi g n tyre secti on wi d th , S, an d th e appropri ate coeffi ci en t: S S−S m in = 0, 96 S sh al l be at l east m m M easu ri n g tyre d i men si on s — Proced u re Before m easu ri n g , m ou n t th e tyre on th e m easu ri n g ri m read y for tyre fi tti n g , i n fl ate to th e recom m en d ed pressu re, an d al l ow to stan d for a m i n i m um of 24 h at n orm al room tem peratu re, after wh i ch read j u st th e i n fl ati on pressu re to th e ori g i n al val u e Tread fi g u rati on s Th ese attri bu ti on s of tread type fi g u rati on s to th e servi ce are to be si d ered as exam pl es on l y Th e ch oi ce of a g i ven tread type fi g u rati on for a g i ven tyre d epen d s on th e tyre m an u factu rer al on e Fi g u re sh ows vari ou s tread fi g u rati on s: tread type A correspon d s to h i g h way servi ce tyres m an u factu red for speed sym bol s P, S an d h i g h er; tread type B correspon d s to h i g h wa y servi ce tyres (for h i g h -perform an ce veh i cl es) m an u factu red for speed sym bol s S an d h i g h er; tread type C correspon d s to tyres for on - an d off-road servi ce m an u factu red for speed sym bol s u p to an d i n cl u d i n g H ; tread type D correspon d s to tyres for excl u si ve off-road servi ce m an u factu red for speed s ym bol M I ©S O – 002 Al l irth gs ersed evr 7 BS AU 50−1.6.1c:2002 I S-1 575 O1 : (1 002)E Fi g u re — Tread fi g u rati on s Tabl e — Coeffi ci en ts for cal cu l ati on of m axi mu m overal l tyre d i m en si on s i n servi ce Coeffi ci en t Tread fi g u ration N OTE a b c 7 a b Type A ,1 a , 07 b Type B ,1 a , 07 b Type C ,1 a ,1 c Type D , 25 ,1 c Coeffi ci en ts for d i ag on al tyres are al so appl icabl e to tyres i n bi as belted stru cti on , 08 for tyres on rim d i am eter code an d bel ow an d , 07 for rad i al tyres Su bj ect to th e d iti on th at D o, m ax − Do i s at l east m m Su bj ect to th e d iti on th at D o, m ax − Do i s at l east m m Tyre l oad -carryi n g capaci ty Tyre l oad -carryi n g capaci ty (TLCC), correspon d i n g to th e l oad i n d ex (see Tabl e 3), i s appl i cabl e for speed s u p to an d i n cl u d i n g km /h 8 © I SO– 002 Al l r i th g sr esed evr BS IAU 50−1.6.1c:2002 S-1 575 O1 : (1 002)E Tabl e — Correl ati on between l oad i n d ex (LI ) an d tyre l oad -carryi n g capaci ty (TLCC) LI 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 TLCC kg 45 46,2 47,5 48,7 50 51 ,5 53 54,5 56 58 60 61 ,5 63 65 67 69 71 73 75 77,5 80 82,5 85 87,5 90 92,5 95 97,5 00 03 LI 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 TLCC kg 06 09 112 115 118 21 25 28 32 36 40 45 50 55 60 65 70 75 80 85 90 95 200 206 21 21 224 230 236 243 LI 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 TLCC kg 250 257 265 272 280 290 300 307 31 325 335 345 355 365 375 387 400 41 425 437 450 462 475 487 500 51 530 545 560 580 For speed symbol “V”, between 21 km/h and 240 km/h, the load-carrying capacity shall be reduced with respect to the value corresponding to the load index as follows: up to 21 km/h: 00 % load 220 km/h max.: 95 % load; 230 km/h max: 90 % load; 240 km/h max: 85 % load I ©SO – 002 All irthgs ersedevr 9 BS AU 50−1.6.1c:2002 I S-1 575 O1 : (1 002)E Between these speeds, linear interpolation is permitted For “VB” and “VR” tyres, the load-carrying capacity above 240 km/h shall be further reduced by % for each km/h increase in speed For “ZR” tyres, the load-carrying capacity is applicable for speeds up to and including 240 km/h The loadcarrying capacity above 240 km/h shall be reduced as follows: 250 km/h: 95 % load; 260 km/h: 85 % load; 270 km/h: 75 % load For speeds over 270 km/h, consult the tyre manufacturer concerned 7 Speed sym bol s Speed symbols shall be as given in Table Tabl e — Correl ati on between speed sym bol s an d speed categ ori es Speed s ym bol J K L M N P Q R S T H V W a Speed categ ory km/h 00 110 20 30 40 50 60 70 80 90 21 240 a 270b Tyres designed for operations at speeds in excess of 240 km/h shall be identified according to 4.4.3, Example For the maximum speed capability, consult the tyre manufacturer b Tyres designed for operations at speeds in excess of 270 km/h shall be identified according to 4.3.3, Example For the maximum speed capability, consult the tyre manufacturer 101 © ISO 002 – Allir thgser sedevr BS IAU 50−1.6.1c:2002 S-1 575 O1 : (1 002)E Cen tri fu g al rad i u s Th e m axim u m cen tri fu g al rad i u s, R d yn , cau sed b y cen tri fu g al force, i s rel ated to th e m axim u m speed of th e veh i cl e, an d sh al l be cal cu l ated as fol l ows: R d yn = 0, D r + H ¥ c wh ere D r i s th e n om i n al ri m d i am eter; H i s th e d esi g n tyre secti on h ei g h t; c i s th e appropri ate coeffi ci en t (see Tabl e 5) For veh i cl es h avi n g m axi m u m speed s i n excess of 240 km /h , su l t th e tyre m an u factu rer Tabl e — Coeffi ci en ts for cal cu l ati on of m axi mu m cen tri fu g al rad i u s at vari ou s m axi mu m d ri vi n g speed s Coeffi ci en t Tread fi g u ration U p to 50 km /h c U p to 80 km /h U p to 21 km /h U p to 240 km /h Types A an d B , 07 a ,1 ,1 ,1 Types C an d D ,1 b ,1 ,1 — a b Su bj ect to th e d iti on th at Hc − H i s at l east m m Su bj ect to th e d iti on th at Hc − H i s at l east m m I ©S O – 002 Al l irth gs ersed evr 111 BS AU 50−1.6.1c:2002 I S-1 575 O1 : (1 002)E An n ex A (i n form ati ve) G u i del i n e val u es for m etri c seri es G u i d el i n e val u es are g i ven for tyre d i m en si on s i n Tabl es A an d A Tabl e A — G u i d el i n e val u es Dim en si ons i n m il l im etres Aspect rati os 00, 90, 80: Ri m /secti on rati o K As pect rati os 70, 65, 60: Ri m /secti on rati o = 0, K As pect rati os 55, 50: Ri m/secti on rati o = 0, K = 0, N om in al Th eoreti cal M easuri ng Desi g n Th eoreti cal M easuri ng Desi g n Th eoreti cal M easuri ng Desi gn secti on ri m wid th ri m wid th secti on ri m wid th ri m width secti on ri m wid th ri m wid th secti on code wi d th cod e wi d th code wi d th wi d th S R 60 121 R R R S R R S m S 36 61 42 59 — — — 70 42 69 49 85 69 — — — 80 48 85 80 56 80 — — — 90 54 90 63 50 90 — — — 00 60 50 01 70 75 00 — — — 110 66 50 09 77 00 110 — — — 20 72 75 119 84 50 22 — — — 30 78 00 29 91 50 29 04 00 29 40 84 50 42 98 00 41 112 50 41 50 90 50 50 05 00 49 20 50 48 60 96 00 62 112 50 61 28 00 60 70 02 00 70 119 50 68 36 50 71 80 08 50 83 26 00 80 44 50 78 90 — — — 33 00 88 52 00 90 200 — — — 40 50 200 60 25 200 N th th m th m © I SO 002 – Al l ir th g ser sed evr BS IAU 50−1.6.1c:2002 S-1 575 O1 : (1 002)E Tabl e A — G u i d el i n e val u es Dimensions in millimetres Desi g n secti on h ei gh t N om i n al secti on wi d th SN 60 70 80 90 00 110 20 30 40 50 60 70 80 90 200 H H S (%) at vari ou s n omi n al aspect rati os / 00 60 70 80 90 00 110 20 30 40 50 60 70 80 — — I ©SO – 002 All irthgs ersedevr 90 54 63 72 81 90 99 08 117 26 35 44 53 65 — — 80 — 56 64 72 80 88 96 04 112 20 28 36 44 — — 70 — — 56 63 70 77 84 91 98 05 112 119 26 — — 65 — — — — 65 72 78 85 91 98 04 111 117 24 30 60 — — 54 60 66 72 78 84 90 96 02 08 — — 55 — — — — — — — 72 77 83 88 94 99 05 110 50 — — — — 50 55 60 — — — 80 85 90 95 00 313 BS AU 50−1.6.1c:2002 I S-1 575 O1 : (1 002)E Bi bl i og raph y [1 ] I S O 4 -1 , Motorcycle tyres and rims (Code designated series) — Part 1: Tyres [2 ] I S O 4 -2 , Motorcycle tyres and rims (Code-designated series) — Part 2: Tyre load ratings [3 ] I S O 4 -3 , Motorcycle tyres and rims (code-designated series) — Part 3: Rims [4 ] I S O 51 -2 , Motorcycle tyres and rims (metric series) — Part 2: Tyre dimensions and load-carrying capacities [5 ] [6 ] I S O 51 -3 , I S O 54 -1 , Motorcycle tyres and rims (metric series) — Part 3: Range of approved rim contours Motorcycle tyres and rims (Code-designated series) — Diameter codes to 12 — Part 1: Tyres [7 ] 141 I S O 54 -2 , Motorcycle tyres and rims (Code-designated series) — Diameter codes to 12 — Part 2: Rims © I S O 0 – Al l i r th g s er s ed evr