TECHNICAL
GUIDE
TECHNICAL SPECIFICATIONS
SMALL TYRES FOR HORTICULTURE
AND AGRICULTURE
Variations of tyre dimensions
``Small tyres for internal transport
``Tyres for ride on mowers
``Tyres with tractor pattern
``Tyres for tedders, forage harvesters etc.
The measurements for diameter and section width
indicate maximum diameter and width including
the possible tyre growth, in use. The measurements
refer to tyres fitted to the recommended wheel
dimension.
180x45
7x1 3/4
200x35
8x1 1/4
200x50
8x2
220x50
8 1/2x2
2.50-3
210x65
8x2.5
3.00-4
260x85
10x3
4.00-4
12x4
2.00-6
10x2
3.50-6
13x3
4.00-6
14x4
2.25-8
12.5x2.25
12 1/2x2 1/4
4.00-8
400x100
5.00-8
Tolerances on these measurements are +7/-4%.
16x4
18x5
6.00-9
21x6
18x8.00-10
195/50-10
20.5x10.00-10
255/50-10
24x8.00-14.5
200/60-14.5
Tyre designations
Dimension
Explanation
3.00-4
Our designation:
Tyre width 3.00” – Rim diameter 4”
10x3
F ormer designation in inches:
Tyre width 3” – Tyre diameter 10” (= 3” x 2 + 4”)
260x85
esignation in millimetres:
D
Tyre diameter 260 mm – Tyre width 85 mm
The former designation in inches converted to mm:
10” x 25.4 = approx. 260 mm
3” x 25.4 = approx.   85 mm
85/100-4
T his is how the designation would be, had it been a passenger
car tyre.
Tyre width 85 mm – Profile 100% – Rim diameter 4
10x3.00-4
merican designation, mainly used for low profile tyres:
A
Tyre diameter 10” – Tyre width 3” – Rim diameter 4”
Conversion - metric to imperial units
Metric
Weight
Length/distance
=
Imperial
1 ton (t) (1000 kg)
=
0.984 ton
1 kilogram (kg)
=
2.2 lbs (pounds)
1 kilometer (km)
=
1 meter (m)
Imperial
=
Metric
1 ton
=
1.016 ton
1 lb (pound)
=
0.455 kg
0.621 mile
1 mile
=
1.609 km
=
1.094 yard
1 yard
=
0.9144 m
1 centimeter (cm)
=
0.39 inch
1 inch
=
2.54 cm
1 millimeter (mm)
=
0.039 inch
1 inch
=
25.4 mm
1 liter (l)
=
0.22 gallon
1 gallon
=
4.545 l
Volume
Conversion – inflation pressure
kPa
bar
kg/cm2
p.s.i.
kPa
bar
kg/cm2
p.s.i.
kPa
bar
kg/cm2
p.s.i.
10
0,1
0,1
1
160
1,6
1,6
23
320
3,2
3,3
46
20
0,2
0,2
3
170
1,7
1,7
25
340
3,4
3,5
49
30
0,3
0,3
4
180
1,8
1,8
26
360
3,6
3,7
52
40
0,4
0,4
6
190
1,9
1,9
28
380
3,8
3,9
55
50
0,5
0,5
7
200
2,0
2,0
29
400
4,0
4,1
58
60
0,6
0,6
9
210
2,1
2,1
30
450
4,5
4,6
65
70
0,7
0,7
10
220
2,2
2,2
32
500
5,0
5,1
72
80
0,8
0,8
12
230
2,3
2,3
33
600
6,0
6,1
87
90
0,9
0,9
13
240
2,4
2,4
35
700
7,0
7,1
101
100
1,0
1,0
14
250
2,5
2,6
36
800
8,0
8,2
116
110
1,1
1,1
16
260
2,6
2,7
38
900
9,0
9,2
130
120
1,2
1,2
17
270
2,7
2,8
39
1000
10,0
10,2
145
130
1,3
1,3
19
280
2,8
2,9
41
140
1,4
1,4
20
290
2,9
3,0
42
150
1,5
1,5
22
300
3,0
3,1
43
LOAD CAPACITY
PR marking
Originally tyres were marked with the exact number of canvas
layers (plies) built into the tyre. This was an indication of the
strength of the tyre. As stronger materials were developed, the
number of layers could be reduced – maintaining the same
strength of the tyre. The designation “Ply Rating” therefore does
not indicate the actual number of layers (plies) in the tyre, but
the number of layers originally required to give the desired
load capacity. When working with PR marked tyres, the actual
manufacturers data must be used to determine the load capacity
in kg (or pounds).
LOAD INDEX / SPEED INDEX
Speed index (SI)
Load Index and Speed Index will gradually replace the PR marking.
Contrary to the PR marking, the LI and SI give unambiguous and
comparable information on the load capacity – independent
of manufacture and dimension – as the codes can be directly
converted to actual values. The tables give an overview of relevant
LI and SI codes.
SI
km/h mph
SI
km/h mph
SI
km/h mph
A1
5
3
D
65
41
Q
160
100
A2
10
6
E
70
44
R
170
106
A3
15
9
F
80
50
S
180
113
A4
20
13
G
90
56
T
190
118
A5
25
16
J
100
63
U
200
124
A6
30
19
K
110
69
H
210
130
A7
35
22
L
120
75
V
240
150
A8
40
25
M
130
81
W
270
176
B
50
31
N
140
88
Y
300
189
C
60
38
P
150
94
Load index (LI)
LI
kg (lb)
LI
kg (lb)
LI
kg (lb)
LI
kg (lb)
LI
kg (lb)
LI
kg (lb)
LI
kg (lb)
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
45 (99)
46,2 (102)
47,5 (105)
48,7 (107)
50 (110)
51,5 (113)
53 (117)
54,5 (120)
56 (123)
58 (128)
60 (132)
61,5 (135)
63 (139)
65 (143)
67 (147)
69 (152)
71 (156)
73 (161)
75 (165)
77,5 (171)
80 (176)
82,5 (182)
85 (187)
87,5 (193)
90 (198)
92,5 (204)
95 (209)
97,5 (215)
100 (220)
103 (227)
106 (233)
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
60
61
109 (240)
112 (246)
115 (253)
118 (260)
121 (266)
125 (275)
128 (282)
132 (290)
136 (299)
140 (308)
145 (319)
150 (330)
155 (341)
160 (352)
165 (363)
170 (374)
175 (385)
180 (396)
185 (407)
190 (418)
195 (429)
200 (440)
206 (453)
212 (466)
218 (480)
224 (493)
230 (506)
236 (519)
243 (535)
250 (550)
257 (565)
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
90
91
92
265 (583)
272 (598)
280 (616)
290 (638)
300 (660)
307 (675)
315 (693)
325 (715)
335 (737)
345 (759)
355 (781)
365 (803)
375 (825)
387 (851)
400 (880)
412 (906)
425 (935)
437 (961)
450 (990)
462 (1016)
475 (1045)
487 (1071)
500 (1100)
515 (1133)
530 (1166)
545 (1199)
560 (1232)
580 (1276)
600 (1320)
615 (1353)
630 (1386)
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
650 (1430)
670 (1474)
690 (1518)
710 (1562)
730 (1606)
750 (1650)
775 (1705)
800 (1760)
825 (1815)
850 (1870)
875 (1925)
900 (1980)
925 (2035)
950 (2090)
975 (2145)
1000 (2200)
1030 (2266)
1060 (2332)
1090 (2398)
1120 (2464)
1150 (2530)
1180 (2596)
1215 (2662)
1250 (2750)
1285 (2816)
1320 (2904)
1360 (2992)
1400 (3080)
1450 (3190)
1500 (3300)
1550 (3410)
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
1600 (3520)
1650 (3630)
1700 (3740)
1750 (3850)
1800 (3960)
1850 (4070)
1900 (4180)
1950 (4290)
2000 (4400)
2060 (4532)
2120 (4664)
2180 (4796)
2240 (4928)
2300 (5060)
2360 (5192)
2430 (5346)
2500 (5500)
2570 (5654)
2650 (5830)
2720 (5984)
2800 (6160)
2900 (6380)
3000 (6600)
3070 (6754)
3150 (6930)
3250 (7150)
3350 (7370)
3450 (7590)
3550 (7810)
3650 (8030)
3750 (8250)
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
3870 (8514)
4000 (8800)
4120 (9064)
4250 (9350)
4370 (9614)
4500 (9900)
4620 (10164)
4750 (10450)
4870 (10714)
5000 (11000)
5150 (11330)
5300 (11660)
5450 (11990)
5600 (12620)
5800 (12760)
6000 (13200)
6150 (13530)
6300 (13860)
6500 (14300)
6700 (14740)
6900 (15180)
7100 (15620)
7300 (16060)
7500 (16500)
7750 (17050)
8000 (17600)
8250 (18150)
8500 (18700)
8750 (19250)
9000 (19800)
9250 (20350)
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
9500 (20900)
9750 (21450)
10000 (22000)
10300 (22660)
10600 (23320)
10900 (23980)
11200 (24640)
11500 (25300)
11800 (25960)
12150 (26620)
12500 (27500)
12850 (28160)
13200 (29040)
13600 (29920)
14000 (30800)
14500 (31900)
15000 (33000)
15500 (34100)
16000 (35200)
16500 (36300)
17000 (37400)
17500 (38500)
18000 (39600)
18500 (40700)
19000 (41800)
19500 (42900)
20000 (44000)
20600 (45320)
21200 (46640)
21800 (47960)
22400 (49280)
Load variation - agricultural implement tyres only
Variation in load carrying capacity with speed
15
20
25
30
35
40
45
A4 LLV
% –>
+65
+20
+12
0
-2
-5
A4 HLV
% –>
+98
+44
+34
+20
+17
+14
A6 LLV
% –>
+65
+29
+21
+14
+7
0
-5
-10
A6 HLV
% –>
+98
+55
+45
+37
+28
+20
+14
+8
A8 LLV
% –>
+65
+40
+33
+26
+19
+12
+5
0
-5
A8 HLV
% –>
+98
+68
+60
+51
+43
+34
+26
+20
+14
Source: ETRTO
10
HLV = High Load Variation
0
LLV = Low Load Variation
km/h
Ag./Impl.
Variations in load carrying capacity with speed and inflation pressure compensation
km/h
0
10
20
30
40
50
60
70
80
90
100
J
% –>
+150
+80
+50
+25
+15
+12
+10
+7
+4
+2
0
Bar/psi
% –>
+40
+30
+21
+13
+10
+8
+6
+2
0
110
120
130
140
150
L
% –>
+110
+75
+50
+35
+25
+20
+15
+12.5
+10
+7.5
+5
+2.5
0
M
% –>
+110
+75
+50
+35
+25
+20
+15
+12.5
+10
+7.5
+5
+2.5
0
0
N
% –>
+110
+75
+50
+35
+25
+20
+15
+12.5
+10
+7.5
+5
+2.5
0
0
0
P
%–>
+110
+75
+50
+35
+25
+20
+15
+12.5
+10
+7.5
+5
+2.5
0
0
0
0
Bar/psi
% –>
+40
+35
+30
+30
+30
+25
+18
+15
+12
+9
+6
+2
0
0
0
0
Bar/psi = Inflation pressure compensation (%)
Source: ETRTO
HLV = High Load Variation
For applications with a great variation in tyre loads. E.g. trailers that cycle
between laden and unladen condition.
Specifically, the tyre load when laden must be at least twice of that
when unladen.
When load figures for a specific tyre are stated as HLV, the figure
indicates the maximum load when fully laden.
LLV = Low Load Variation
For applications with no or rather small variation in tyre loads. E.g.
agricultural implements.
Specifically, the tyre load when maximum laden would not exceed
double of the tyre load when minimum laden.
Rules apply for each individual tyre
On a given machine, tyres on different axles could be running on
different load cycles - i.e. one axle could be HLV whereas another could
be LLV.
As examples, this goes for dumpers, loaders etc., where the front axle
(next to forklifts or shuffle) could be HLV and the rear axle would be LLV.
LOAD, INFLATION PRESSURE AND SPEED
General information - Warnings!
Technical specifications in this catalogue are mainly based
on manufacturers data or the ETRTO, European Tyre and Rim
Technical Organization or STRO standards, Scandinavian Tyre and
Rim Organization and serve as general, basic information.
For every specific tyre and/or wheel, instructions and figures on
load, inflation pressure, speed etc. stated on the product itself, or
by the manufacturer, must be complied with.
For complete wheels, the maximum load, cold inflation pressure
and speed is always determined by the part (tyre or rim/wheel)
having the lowest capacity.
E.g. the load, cold inflation pressure and speed imposed
on the rim or wheel must never exceed the rim and wheel
manufacturers recommendations, even though the tyre might be
approved for a higher load, inflation pressure or speed.
Tyres, tubes and wheels must be used for the intended area of use
only, unless otherwise specified or permitted.
If any doubt, please consult the ETRTO or STRO technical manuals,
or contact us.
Do not mount, inflate or use any tyre/wheel combination, until all
possible doubts have been eliminated.
The STARCO Group will accept no liability due to errors, omissions
or faulty information in this catalogue.
All figures are subject to change without further notice.
Manufacturer’s, ETRTO or STRO specifications are final.
TYRES OVERALL DIAMETER AND SECTION WIDTH
General information - Warnings!
The tyre diameter and tyre section width increase naturally during
normal service. It is therefore important that the intended vehicle
is checked for sufficient clearance to allow for growth - if in any
doubt, consult STARCO for details.