. All Hoosier bias ply tires
with a chalk-mark, follow this same process.
Now, how should the chalk mark be interpreted? It should be viewed as a reference point
or a guide on purchasing tires by size to attempt to attain a certain stagger. Say for
instance, you needed to replace your right front tire. Your car currently has 1" of
stagger (with the RF @ 28 p.s.i.) but you want to get 1 1/2" of stagger. The tire you
were replacing had an original chalk mark of 86", and had a roll out, of say,
85". Obviously, you would want to purchase a tire bigger than the 86" tire you
removed. Most likely, a tire with a chalk-mark of 86 1/2". You have to remember there
are many factors that go into what size a tire will actually measure. The ambient
temperature that day, the air pressure in the tire, whether the tire is new or old. These
are factors that no, one person, controls. You just need to be aware of their existence
and work with what you know. The chalk mark does not tell you the circumference of the
tire at running pressure, it does not tell you how big a tire will grow to, it tells you
that a tire is either going to be bigger or smaller than another one with a different
chalk mark. It's just that simple. Bias ply tires, by nature, are going to vary in size,
whether you buy a Hoosier or the competition's tire. By keeping good records, using common
sense and understanding how the chalk-mark Hoosier tires provide, you will be step ahead
in selecting the proper sized tire(s) (Top)
3. How do I get Hoosier decals for my race car?
If you send us an e-mail at email@example.com
requesting the decals, we would be happy to send them to any of our
customers free of charge to anywhere in the United States or Canada. Remember to include your mailing
address where you want the decals sent. To help defer the cost and avoid
waste please tell us in the e-mail whether you want BLACK,
WHITE or PURPLE decals. You may also want to include the type of racing
you are involved in which will help us determine the proper decals to
send you. We appreciate your Hoosier support by displaying our
name proudly on your race car. (Top)
4. What rim width should I use for my application?
The answer depends on which type of tire you are using.
For our radial tires a good rule of thumb is to take the tread width
dimension (+-) 1/2 inch. This will put you in the optimum range for the
tire. The tire will mount on a wheel outside of this range, however
performance and wear may be negatively affected.
If you find that your vehicle, or the rules, will not allow a wide
enough wheel for the tire you think you would like, consider using a
narrower tire. In most cases a properly sized wheel/tire combination
will outperform a wider tire on a wheel that is too narrow.
If you are looking at our DOT bias racing tires the tolerance is a
bit broader. For our DOT bias line we publish a "measured rim"
or "design rim" dimension. This dimension simply indicates the
width of the wheel the tire was mounted on when the other listed
dimensions are recorded.
Bias ply tires are more tolerant of a range of wheel sizes.
Typically, the listed rim dimension is a good starting point. The wider
tires can range (+-) an inch without noticeable change in performance. A
narrow (less than 6" wide) tire will tolerate (+-) 1/2 inch.
This would also apply to the Historic product line in our tire specs.
In the Road Racing section of our product line the racing slicks are
typically designed for specific applications where the wheel width is
controlled. The tire is designed to perform at its best on the wheel
listed in the "design rim" or "recommended rim"
column. Once again, there is a tolerance for this dimension. The tire
will mount on a different sized rim but, may exhibit unusual wear or
stability outside of the recommended rim.
This is particularly important on "cantilevered" tires.
This is a specific type of construction used in racing classes which
have very narrow wheel restrictions. The design of the tire allows the
usable tread to far exceed the width of the wheel. These tires should
ONLY be mounted on the rim sizes indicated in the specs.
Follow-up question,...Why are the listed rim dimensions different
than the recommendations?
Whenever a D.O.T. tire spec is published there are Tire & Rim
Association guidelines for the specific rim size for a particular tire.
This is intended to standardize the information so that it is possible
to compare one brand of tire to another.
For performance uses these Tire & Rim Association recommendations
may not reflect a best choice or the designed application. (Top)
5. Does it matter which
direction I mount my Hoosier RACE TIRES?
6. How do I know when it is time to replace my
R7/A7 competition radials?
Located on the tread surface of the tires are small divots
or holes. These divots are called tread depth holes and are used to
measure the wear of tread. Tread depth is usually referred to in 32nds
of an inch. A brand new tire should measure 4/32 of depth in each of the
holes. By keeping track of the number of laps on each set of tires and
measuring the depth of tread, you can calculate how much wear is left in
the tires. When the holes are completely flush with the tread, it is
definitely time to change to a new set of tires. There is tread rubber
under the depth hole and the tire can continue to be run, but the driver
must be aware the performance level will be at its lowest. When this
rubber below the depth hole is gone, you will then see the first layer
of cords. At this point, the safety of the tire is now compromised and
the worn tires should be replaced.
The driver must be the ultimate measure of when to
replace the tires. There might be measurable tread depth on the tire,
but the performance (grip or handling) of the tire might be low. To get
the most wear out of your R7/A7 competition tires, be sure to
rotate front to rear or side to side after an event. (Top)
Care Tips for A7/R7 tires
are the do's and don'ts when storing Hoosier race tires at the end of
the racing season?
The useful life of a tire, whether mounted or dismounted, is directly
affected by storage conditions. Tires should always be stored indoors in
a dark, cool, dry room.
1 Remove the tires from the vehicle.
2. Remove the air from the tires and store them on their side in a cool/dark/dry
3. Place tires in a black plastic bag when stored during
4. Make sure the temperature range in the storage
location is between 40-90 degrees Fahrenheit.
1. Don't store tires in direct sunlight or near electric
motors. (Electric motors emit small amounts of ozone.) Tires need to be
protected from light, especially sunlight. Light causes ultraviolet
damage by breaking down the rubber compounds. The storeroom should not
contain electrical welding or any other equipment that could produce
2. Don't apply any chemical treatments to Hoosier tires.
(It's not necessary and may actually damage the integrity of the tire by
breaking down the rubber properties of the tire.) Tires must not be
allowed to come in contact with oils, greases, solvents, or other
petroleum products that cause rubber to soften or deteriorate.
3. Don't store tires in sub-freezing temperatures for
any length of time. (The rubber can freeze and may crack as a result.) (Top)
I would like to sell Hoosier tires in the US or Canada, how do I become
a Hoosier Tire Dealer?
Hoosier has an established
network of independent Hoosier Distributors. They, in turn, establish
their own network of Hoosier Dealers. You will need to contact the
Hoosier Distributor in your area who handles the particular tire line
you are interested in carrying. You will ask the Distributor whether
they have a need for a dealer in your particular location.