Date: Tue, 27 Oct 1998 13:30:11 -0800
Reply-To: Ari Ollikainen <Ari@OLTECO.COM>
Sender: Vanagon Mailing List <vanagon@vanagon.com>
From: Ari Ollikainen <Ari@OLTECO.COM>
Subject: Re: Tire Load Index
Content-Type: text/plain; charset="us-ascii"
>Ari Ollikainen wrote:
>>
>> In response to my posting of a load index for values of 71-110,
>> at 9:15 PM 10/26/98, David-M wrote:
>>
>> >There is also some law that says that for a passenger tire on a truck,
>> >you have to reduce the load rating by 10%. That definitely applies to
>> >the Vanagon.
>>
>> That's interesting...whose law is it, who does it apply to, and
>> can you provide a cite?
>>
>Go here:
>
>http://www.roadmastertire.com/cooper/discover.htm
>
>It may not be a law, just an industry standard, but I am sure there is
>good reasoning behind it.
Fascinating chart, especially the 35psi tire pressure for the
Cooper Discover tires, is that MAX?
It's the industry (Tire and Rim Association) covering its behind
(by 10%?...hardly seems worth it). Interestingly the 10% reduction
is for the NorthAmerican P-Metric tire sizes used "in light truck
services" and doesn't apply to the European metric (no P in front,
as in 205/70 versus P205/70) sizes...not that it matters, since
Cooper doesn't make the Discover in a metric.
Once more, it all depends on the definition of "light truck services".
Regardless, in my opinion, stinting on tires is pure foolishness.!
BTW, there actually <GASP!> is a CANADIAN law that specifies the
derating for non-passenger car uses of passenger car tires somewhat
obscurely (and results in a reduction of 9% due to the calculation
method!):
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[http://www.tc.gc.ca/actsregs/mvsa/english/mvsr120.html]
Motor Vehicle Safety Act
Motor Vehicle Safety Regulations
Standard 120
Tire Selection and Rims for Vehicles
Other Than Passenger Cars
120. (1) Subject to subsection (5), the tires of every bus,
chassis-cab, motorcycle, motor driven cycle, moped, multipurpose
passenger vehicle, trailer, trailer converter dolly and truck shall
meet the requirements of the Motor Vehicle Tire Safety
Regulations.
(2) Every motor vehicle described in subsection (1) shall be equipped
with rims that are listed by the manufacturer of the tires as
being suitable for use with the tires of the motor vehicle in
accordance with subsection 1(1) or 2(1) of Schedule V to the Motor
Vehicle Tire Safety Regulations.
(3) The sum of the maximum load ratings of the tires fitted to an axle
shall
(a) be not less than the gross axle weight rating (GAWR) of the axle
system as specified in the vehicle's statement of compliance label as
required by section 6 of the Regulations;
(b) where the statement of compliance label shows more than one GAWR
for the axle system, be not less than the GAWR corresponding to the
size designation of the tires fitted to the axle; and
(c) where the size designation of the tires fitted to the axle does
not appear on the statement of compliance label, be not less than
the lowest GAWR appearing on the label.
>>>>> (4) For the purpose of determining the sum referred to in subsection
>>>>> (3), where a bus, chassis-cab, multipurpose passenger vehicle,
>>>>> trailer, trailer converter dolly or truck is equipped with a passenger
>>>>> car tire, the maximum load rating of that tire shall be
>>>>> divided by a factor of 1.10.
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OLTECO Ari Ollikainen
P.O. BOX 3688 Networking Technology and Architecture
Stanford, CA Ari@OLTECO.com
94309-3688 415.517.3519