2009 DT BOOK ONLINE

TYRE TECH TALK
by Bruce de Kock, owner of Bike Tyre Warehouse Group
ALL THE PREMIUM BRANDS
THAT COUNT UNDER ONE ROOF
Chances are good that you will need
to refer back to this feature every once
in a while. There is a lot of info, but it
is important – and relevant, no matter
what bike you ride.
The Basic’s of Reading a Tyre:
Wow! Provinces open & the sun is
shining. Rider’s are getting back onto
their bikes in full force to hit the countryside
and enjoy the open road.
If you have been off your bike for a
while, make sure that you give it a
good scrutineering when you are dusting
it off in the garage.
Critical is to check your tyres if your
bike has been standing for the last
6 months.
If you’re not sure about the condition
of your tyres, pop into a reputable
motorcycle tyre fitment centre and
have them checked out. The Bike Tyre
Warehouse Fitment Centre Group will
give them a free inspection and check
you have the correct specification
tyres for your bike as well as the correct
tyre pressures before you head off
into the sunrise or sunset.
If you need new rubber, here is a very
basic guide to reading a tyre.
It is important for you to take the time
to run through this content as it will
assist you in making the correct choice
by that I mean not the brand of tyre
but the type of tyre specific to your
bike and your bikes requirement which
could - essentially save your life.
We can’t tell you the number of times
that riders come in with issues concerning
road handling, road noise, tyre
life etc – and it is usually because they
have fitted the incorrect tyre/s to their
bikes, 90% of the time due to
ignorance about the basics of motorcycle
tyres.
HOW TO READ A TYRE’S MARKINGS :
1.Tubeless: No tube is used, when
mounted on a tubeless rim; abbreviated
“TL”
2.Rear: Direction of rotation for rear
tire, indicated by an arrow on the tire
sidewall
3.Michelin: Tire manufacturer
4.73 Load index: For example, 73 corresponds
to a load of 805 pounds (365kg)
per tire
5.Radial
6.Pilot Power 3: The tire’s model name
7.190: Nominal section width of the tire,
expressed in millimeters
8.55: Aspect ratio, the sidewall height
as a proportion of the tire width
9.R: Radial construction
10.17: Bead-seat diameter of the wheel,
expressed in inches (1 inch = 2.54 cm)
Let’s kick off with the tyres LOAD INDEX
which is a numerical code associated with
the maximum load that a tyre can carry at
the speed indicated by its Speed Symbol
under service conditions specified by the
tyre manufacturer.
This is important, and more especially so if
you are carrying more than just the weight
of the bike and yourself. Loading your panniers,
the wife’s kitchen sink, pillion etc. all
has a dramatic effect on the tyres capability
to do what it needs to under load.
Again the amount of times bikes come
in with tyres that are totally incapable of
carrying a load, sport touring heavy weight
motorcycles especially.
The table to the right is self-explanatory
so have a look see and check that the
tyres you have on your bike are the
correct load index.
Just as important is the SPEED INDEX
which indicates the maximum speed at
which the tyre can carry a load corresponding
to its Load Index under
service conditions specified by the
tyre manufacturer.
Load index Load index Speed index
Every bike requires tyres with a specific
speed index. The table below defines the
maximum speed at which a tyre can carry
the maximum load indicated by its load
index under the conditions of use specified
by the manufacturer.
The maximum speed is clear when the
speed rating is defined e.g. J = 100, S =
180, H = 210 etc.
The (W) speed index is not restricted,
(known as unbounded, shown by the use
of brackets around the speed index letter,
the tyre manufacturer must be able to
supply the maximum speed capability of
the tyre.
It is important to know the maximum speed
capability of the bike before a (W) speed
rated tyre is fitted. If the bike is capable of
a higher speed than the tyre is, the rider
MUST be warned of this.
This is also a consideration for off road
biased DUAL SPORT TYRES such as the
Michelin Anakee Wild.
In some cases the speed index is lower on
the Anakee Wild than the speed capability
of the bike and the OE tyre fitment.
Riders MUST be warned of this fact yet
again ignorant tyre sellers do not do this,
so it all comes down to you as the rider
knowing the basics and servicing your
bikes tyre requirements by professionals
who specialize in motorcycle tyres and
have the knowledge to advise you on the
correct set up for your bike.
I have decided to tackle quite a few topics
concerning tyre technology related to
capability & safety in the future. There are
some specific subjects I have written about
over the years which now need revised
detail as the capability and technology of
motorcycles has increased substantially
and so does the tyre technology therefore
it’s about updating and increasing your
knowledge base.
So many times I read the write ups on the
new bikes hitting the market, most of the
time mention of the tyres is only made if it
is a well-known brand that is OEM fitment
or if a brand importer has sponsored tyres
for the bike test. Sometimes I have noticed
that even the test tyres sponsored have
not been the correct specification tyre type
for the bike.
Education is key and the Bike Tyre Warehouse
Group is driving motorcycle tyre
education in your interests; we are always
available to discuss your concerns, so pop
in at any of our branches and talk to the
professionals.
www.biketyrewarehouse.com
A Big Thank you to Ryan Robertson –
Business Development Manager, Auto
Cycle Centre JHB for sponsoring this
September Tyre Tech Talk in the interests
of promoting rider safety.
More than most, bikers have felt the lock
down as we are so used to our freedom
and open roads so enjoy the sunshine &
ride safe.
Bruce de Kock – Managing Director - Bike
Tyre Warehouse Group Holdings Pty Ltd
Tel: 011 205 0216 • Cell: 073 777 9269 / 083 467 1349
Unit 9 Sable Park, 997 Richards Drive, Midrand
Facebook @BikeTyreWarehouse • Twitter @biketyrewhse
www.biketyrewarehouse.com