User Manual

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The speed rating of a tire
indicates the speed category
(or range of speeds) at which
the tire can carry a load under
specied service conditions.
The speed rating system
used today was developed
in Europe in response to the
need to categorize tires into
standardized speeds. A letter
from A to Z symbolizes a
tire’s certied speed rating,
ranging from 5 km/hr (3
mph) to above 300 km/hr
(186 mph). This rating system
(see chart on this page)
describes the top speed for
which a tire is certied.
When this speed rating
system was originally
developed, the Unlimited
V category of over 210 km/
hr (130 mph) was the top
speed rating a tire could
achieve. As manufacturers made more tires that t into this category, it was
necessary to better regulate performance at standardized speeds to help
ensure safety. The Limited V category of 240 km/hr (149 mph) was then
created, and the Z or (Y) speed rating was added as the top speed rating
that a tire could achieve. W and Y limited speed symbols have been added as
higher speed categories.
Always consult the tire manufacturer for the maximum speed of Unlimited
Z or (Y) tires. Speed rating is identied as a part of the tire’s sizing or service
description. Exceeding the lawful speed limit is neither recommended nor
endorsed.
In the latest attempt to standardize tire designations, all ratings except
Unlimited Z incorporate the speed symbol and load index as the tire’s service
description.
For Example:
205/60R15 91V
205 = Section Width in Millimeters
60 = Aspect Ratio
R = Radial Construction
15 = Rim Diameter in Inches
91V = Service Description (Load Index and Speed Rating)
Speed
Symbol
Speed
(km/hr)
Speed
(mph)
L
120 75
M
130 81
N
140 87
P
150 94
Q
160 100
R
170 106
S
180 112
T
190 118
U
200 124
H
210 130
V
240 149
W
ZR
270 168
Y
300 186
(Y)
Above 300
Above 186
(consult tire manufacturer)
SPEED RATING SYSTEM
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