."\ tyre.1 .TH TYRE P "Manual V1.1 for Program V1.0 1998.10.21" "Julian H. Stacey" "Julian H. Stacey, http://www.berklix.com" .\" A4 the cludgy way. .pl 29.6c .UC 4 .SH NAME tyre \- Determine outer size of a car tyre (tire) in millimetres. .SH SYNTAX .B tyre .SH SUMMARY .I tyre Tiny program to determine outer size (width + 2 x diameter of a car tyre in millimetres. .SH DESCRIPTION ('Tire' is the American spelling, included for search engines) .br When one buys new snow chains for car tyres, one has to find ones that will fit. Chains if bought new, should have a label quoting several sets of tyre geometries it will fit. .\" INSERT EXAMPLES HERE If wheels are of an unusual size, they may not be found in the chain manufacturer's list of common sizes, but maybe chains might fit anyway ? Maybe you have unlabelled chains from another car, know they used to fit a particular wheel size, & want to know if there's a chance they might fit your new wheel size ? but you don't want to get cold oily rusty filthy chains stuck to your skin & clothes, if no chance they will fit ? So first use this tiny programme to do an estimate of the geometry. Tyre Manufacturer number triplets do Not give outside diameter, but use a nasty combination of Metric millimetres And Imperial Inches. This program calculates geometry to help you. What may interest you most is trading a bit off the tread width for a bit on the outside diameter, or vice versa.) WARNINGS / DISCLAIMERS .in +2 The code or description may not match reality, but it's better than guess before trying the rust at sub zero ;-). Code may not match the description. (Read the code, tell me if I got something wrong). If you don't understand, do Not use this programme. I disclaimer all & every liability, go elsewhere to get certification, Use your common sense ! Some jurisdictions might only allow you to use chains that match "officially" Do Not assume chains will fit properly just because numbers are similar (After all, some set of summer tyre numbers would produce a match for some winter tyres, but if you put the chains on a low profile summer tyre with aluminium hubs, it would abrade the aluminium, & maybe catch & snap). Loose chains might not grip tyre well enough, causing loss of traction downhill & up, & damage to rubber if going up a steep hill, tyres slipping in chains. Loose chains can flap, catch on the car, damage, snap, wrap round axle or brake pipes, use your imagination & common sense. .in -2 Consider a theoretical single piece of chain stretched from axle, out round the tyre & back to axle: Each extra 1cm of radius takes 2cm of chain otherwise available for tread width: so 2 * radius + width might be a meaningful equivalent for matching triplets. For each extra 1cm of radius (ie 2 cm of chain across tyre tread) you will also need 2 * 3.14 * 1cm of extra circumferential chain. Further consider that the average chain around the circumference is some approximation between a set of squares on the centre of a tyre, & a diamond lattice around the curved edge of tyre. So as the circumference of the tyre grows, if we assume a 45 degrees diamond each extra 1 cm of circumference pull on the diamond around the circumference deprives each of 2 side walls of 1cm of chain. However, its a cross between a diamond & a square, so halve the effect, assume 1 cm of increased circumference takes not 2 but just 1 extra cm of sidewall chain. What you need are chains with about the same circumference = 3.14 * Diameter, & an addition of width + 2 * radius that match yours, (because every extra 1 cm. of radius use 2 cm. of chain across the tread). So this program emits 2 numbers: Circumference & Diameter+Width. .ft B Some tyre examples: .ft R .in +4 .nf \" { AAA/BB CDD EE F .\"---------------------------------------------------------------------------- 175/70 R13 82 H : Summer Tyre, Old Car. \" Same geometry for both. .\"---------------------------------------------------------------------------- 175/70 R13 82 T : Winter Tyre, Old Car. \" Same geometry for both. .\"============================================================================ .\" New Car: Subaru Trend Fahrzeugschein: 29.07.1998 .\" 195/60 R15 87 V .\" 205/50 R16 87 V .\" #16: zu Achst Kg: v:950 m:- h:1040 .\" Explanation at http://de.wikipedia.org/wiki/Fahrzeugschein .\"---------------------------------------------------------------------------- 205/50 R16 87 V Bridgestone : 1st Summer Tyre, New Car.\" (original) .\" Potenza RE030, EP 3V, DCB517 .\" Made In Japan, T9701 E030 Z, .\" Tubeless, Steel belt radial, E4, 020647, (Tread) 008 .\" Sold on new Japanese large limousines .\" Bridgestone: A Manufacturer .\" Potenza: A brand name of manufacturer. .\" RE 030: Tread type. .\"---------------------------------------------------------------------------- 205/50 ZR16 87 W Rain Sport2 UniRoyal : 2nd Summer Tyre, New Car. \" Tyres bought 2008-07-09 .\"---------------------------------------------------------------------------- 195/60 R15 88 H MS plus 66 Uniroyal : 2nd Winter Tyre, New Car \" Bought 2009-01-22 .\" Continental Winter Contact, 195/60 R15 RAD, 88 H, M+S Tubeless, .\" E4 026940, Max Load 560 Kg 1235 lbs, .\" Max Pressure 300 KPI 44 PSI (40 with seat beeds ) .\" Tread Ply: 1 Poly + 2 steel + 2 Nylon, Side Ply: 1 poly. .\" ---------- .\" V means 240, H means 210, but Fahrzeugschein box 6 says max 200 Km/hr. .\" So I convinced Dekra I didnt need a 210 sticker on dash board. .\" Fahrzeugschein says: .\" 195/60 R15 87 V .\" 205/50 R16 87 V .\"---------------------------------------------------------------------------- .\" Munich vendors: .\" http://www.reifen.com .\" http://www.atu.de .\" Some UK tyre vendors: .\" pit stop .\" http://www.freewayfastfit.co.uk .\" http://www.national.co.uk largest independent fast-fit tyre specialist. .\" http://www.kwik-fit.com .\" http://www.setyres.com .\" http://www.ststyrandexhaust.co.uk .\" http://www.watlingtyres.co.uk .\"---------------------------------------------------------------------------- .\" Manufacturers: .\" http://en.wikipedia.org/wiki/Dunlop_Tyres .\" http://en.wikipedia.org/wiki/Hankook_Tire .\"---------------------------------------------------------------------------- .fi \" } .in -4 Explanation .nf \" { .in +4 A Width of tyre in millimetres B Ratio of Height of rubber tyre, to width of tyre. C Radial: All modern high speed tyres are, (however old & slow tyres may be cross-ply) D Inner diameter in Inches. E Load Index (LI): Maximum Kilograms Per Tyre, .fi \" } .in +2 65:290, \" Source: http://www.kwik-fit.com 66:300, \" Source: http://www.kwik-fit.com 67:307, \" Source: http://www.kwik-fit.com 68:215, \" Source: http://www.kwik-fit.com 69:325, \" Source: http://www.kwik-fit.com 70:335, \" Source: http://www.kwik-fit.com 71:345, \" Source: http://www.kwik-fit.com 72:355, \" Source: http://www.kwik-fit.com 73:365, \" Source: http://www.kwik-fit.com 74:375, \" Source: http://www.kwik-fit.com 75:387, \" Source: http://www.kwik-fit.com 76:400, \" Source: http://www.kwik-fit.com 77:412, \" Source: http://www.kwik-fit.com 78:425, \" Source: http://www.kwik-fit.com 79:437, \" Source: http://www.kwik-fit.com 80:450, \" Source: http://www.kwik-fit.com 81:462, \" Source: http://www.kwik-fit.com 82:475, \" Source: http://www.kwik-fit.com 83:487, \" Source: http://www.kwik-fit.com 84:500, \" Source: http://www.kwik-fit.com 85:515, \" Source: http://www.kwik-fit.com 86:530, \" Source: http://www.kwik-fit.com 87:545, \" Source: http://www.kwik-fit.com 88:560, \" Source: http://www.kwik-fit.com My winter tyres confirm 560 Kg 89:580, \" Source: http://www.kwik-fit.com 90:600, \" Source: http://www.kwik-fit.com 91:615, \" Source: http://www.kwik-fit.com 92:630, \" Source: http://www.kwik-fit.com 93:650, \" Source: http://www.kwik-fit.com 94:670, \" Source: http://www.kwik-fit.com Confirmed elsewhere 95:690, \" Source: http://www.kwik-fit.com 96:710, \" Source: http://www.kwik-fit.com 97:730, \" Source: http://www.kwik-fit.com 98:750, \" Source: http://www.kwik-fit.com 99:775, \" Source: http://www.kwik-fit.com 99/98 1709 pounds = 770 Kg () 100:800, \" Source: http://www.kwik-fit.com 101:825, \" Source: http://www.kwik-fit.com 102:850, \" Source: http://www.kwik-fit.com 103:875, \" Source: http://www.kwik-fit.com 104:900, \" Source: http://www.kwik-fit.com 105:925, \" Source: http://www.kwik-fit.com 106:950, \" Source: http://www.kwik-fit.com 107:975, \" Source: http://www.kwik-fit.com 108:1000 \" Source: http://www.kwik-fit.com .in -2 .nf \" { F Maximum sustainable speed. (from http://www.reifen.com) .\" Also see: .\" http://www.tiresplus.com/tires/tire-buying-guide/tire-speed-rating/ .\" http://www.theaa.com/driving-advice/safety/tyre-speed-rating .\" http://www.theaa.com/driving-advice/safety/tyre-life-and-age GI km/h MPH .\" http://www.uniroyaltires.com/assets/pdf/tire-safety-maintenance.pdf A B C D E F G 90(&) ( 56mph) I J K 110 ( 68mph) For large commercial vehicles L 120(&) ( 75mph) M 130 ( 81mph) N 140 ( 87mph) O P 150 ( 93mph) Q 160 ( 99mph) Low speed (vans etc). Lowest normally used for cars. R 170 (106mph) S 180 (112mph) T 190 (118mph) U 200 (124mph) H 210 (130mph) Max in German allowed to be puncture repaired. V 240 (149mph) No puncture repairs allowed in Germany. VR >210 (>130mph) No puncture repairs allowed in Germany. W 270 (168mph) No puncture repairs allowed in Germany. Y 300 (186mph) No puncture repairs allowed in Germany. X Y Z ? (*) ZR >240 (>149mph) No puncture repairs allowed in Germany. M+S Matsch+Schnee (slush & snow) OWL Outlined White Letter sidewall RWL Raised White Letter sidewall T/T Tube Type T/L Tubeless Type XL Extra load HP & UHP [Ultra] High Performance Usually have rotation arrow. TPMS (Tire Pressure Monitoring Systems) (RDKS in German, compulsory on new German cars from 2014/11) TWI Tread Wear Indicator at 1.6 mm .\" http://www.reifen.com/de/faq/abc http://www.reifen.com/en/faq/abc DoT US Department Of Transportation Manufacturer date. "327" = Week 32 in 1997. 1614 = Week 16 in 2014 EMT Extended Mobility Technology Fully deflated can run 80 km @ 80 km/hr (when perhaps then useless). Run Flat technologies have various names (& only to be used with matching cars woth detection via ABS, or in rim bed or valve) : - DSST = Dunlop - EMT, ROF = Goodyear - Run Flat = Bridgestone - SSR = Continental - ZP = Michelin. .\" ------- Reinforced Vans & Mini busses & fast cars with V tyres, for more weight, but they also have a higher load index. Need more pressure. .\" http://www.reifen.com .\" Reinforced Reifen .\" Bezeichnung an Reifen besonders hoher Tragfähigkeit (z.B. .\" für Kleintransporter, Kleinbusse, Vans, Geländewagen, .\" schnelle Pkw mit V-Reifen). Ausschlaggebend ist aber auch .\" hier die entsprechend höhere Load Index-Kennziffer. .\" Reinforced-Reifen einer bestimmten Dimension benötigen auch .\" einen höheren Fülldruck als die Standardversion des Reifens. .\" ------- RSC Run-Flat System Component .\" http://www.reifen.com .\" Runflat Reifen .\" Die Notlaufeigenschaft wird durch eine verstärkte Seitenwand, .\" welche im Falle eines Luftdruckverlustes die Reifenform .\" erhält und somit das Abspringen des Reifens von der Felge .\" verhindert, erreicht. D.h., dass im Falle einer Panne die .\" Weiterfahrt des Fahrzeuges bis zu 250 km bei einer .\" Geschwindigkeit von bis zu 80 km/h möglich ist. .\" .\" Alle Run-Flat-Reifen tragen das einheitliche RSC-Symbol .\" (Run-Flat System Component) an ihrer Seitenwand. Run Flat .\" Reifen benötigen keine speziellen Felgen, dürfen aber nur .\" auf Fahrzeugen eingesetzt, werden, die mit einem funktionierenden .\" Luftdruckkontrollsystem ausgestattet sind. .\" ------- (*) = Information from manufacturer "Continental" (&) = Information entry from vendor reifen-fix.de. .fi \" } .in -4 .\"------- .\" caravan@RAS .\" From Ron From Web or jhs .\" made in korea .\" HANKOOK .\" RAO 8 Radial PlyRating=8 .\" 175 14 C Size=175 R14 .\" 99/98 Q Index=99/98 Q .\" Max load 1709 pounds ( = 770 Kg .\" 65 PSI .\" Web Refs .\" http://www.hankooktyre.com.au/products/product_search.asp?search=175 .\" http://www.hanta.co.kr/hantax/english/tire_product/tire/index_02.html .\"------- Tread Minimum, Legal limits: Germany Laufleistung (@ 2014 from http://www.reifen.com/de/faq/abc http://www.reifen.com/en/faq/abc) is 1.5mm. Mindestprofiltiefe 1,6 mm for whole width of tyre, Europe wide. If 1.6, aquaplanning distance will be double that of a new tyre. Summer tyres for sfatey reasons should be change dlatest at 2mm, winter at 4mm. & not more than 10 years old. Britain I recall was 1/10 inch ie 2.54mm. Do not mix different tread types on same axle. (My Subaru dealer says for Legacy 4WD, keep all 4 tyre manufacturers etc the same to avoid eg different height of tyres causing stress on the 4 wheel drive.) My snow chains for old car, quoted as: .\" Manufacturer Rud. Item Code 97 917 Other number 45 117 .\" 2 packs of 2 in plastic box @ DM 320/pair < ADAC Sendlinger Tor 12.1985 .in +4 .nf \" { 175/70-13\0\0\0165\0\0\0-13 145/\0\0-14\0\0\0155\0\0\0-14 165/70-14\0\0\0135\0\0\0-15 145/\0\0-15 .in -4 .fi \" } .\"------- My snow chains for new car, quoted as: .\" Purchased 12.2001 DM 134 inc mwst @ ATU, Model ARK6 05 or 15 .in +4 .nf \" { Yet to type in. .fi \" } .in -4 .\"------- .nf \" { .I Tyre examples of program Input : Output .in +4 .ti -2 Old car .br 175/70 13 : outer_diam_mm=575, o_diam+width_mm=750 .ti -2 Old chains alternate 165 70 14 : outer_diam_mm=586, o_diam+width_mm=751 .ti -2 New car winter tyres .ft B 195 60 R15 : outer_diam_mm=615, o_diam+width_mm=810 .ft R New car summer tyres .ft B 205/50 R16 : outer_diam_mm=615, o_diam+width_mm=810 .ft R .fi \" } .sp PS .br Aluminium Versus Steel Wheel Rims: .in +4 Obviously a lighter wheel spinning fast is easier to turn; but rubber tyre weight probably makes difference between different metal weights not so significant, especially as metal rim in middle, where less significant for rotational inertia (for calculations: square of radius), whereas rubber weight further out.. .sp Germans use steel wheels/ rims on winter tyres, aluminium (or steel) on summer tyres. I've never heard of aluminium rims used on winter tyres, aluminium would damage from snow chains. .sp As aluminium is weaker than steel (but doesn't rust (well not as such though some corrosion occurs)) aluminium rims are thicker, so reducing any weight advantage of less dense metal; Just as aluminium cycle frames aree thicker than steel bikes, so I'm not really sure hom much benefit aluminium has over steel, especially as more expensive. .sp Personally I reckon my old car, driving in summer with winter tyres, felt about twice as sloppy, & more wind drift if sudden side wind at speed. .sp Some Winter (& some Summer) tyres have a V profile, so don't mix left & right tyres: else instead of throwing slush out sideways, you'll slither on top of it ! .in -4 .SH BUGS Theory may be half baked. See all disclaimers. .SH Nomenclature English & American & German: "Car" = "Auto" = "PKW/Privat Kraft Wagen", "tyre" = "tire" = "reife", "exhaust" = "muffler" = "auspuff", "bonnet" = "hood" = "?", "boot" = "trunk" = "?", "engine" = "motor", "petrol" = "gas" = "benzin" American law requires their "tire" manufacturers to produce more information on the side of their tires, than British tyre manufacturers need to. MS, M+S, M/S or M&S : Mud and Snow Designation of Rubber Manufacturers Association (RMA) http://en.wikipedia.org/wiki/Rubber_Manufacturers_Association .SH OPTIONS None .SH EXIT CODE 0 for success if 3 numerics are read, else 1. .SH COPYRIGHT Program & Document Copyright Julian H. Stacey, Munich, 1998.10.21. .br Free Use, but I disclaim all liability ! .\" .so author.jhs .SH FILES None. .\" End of file