Evening star., 1933-06-25
GOOD DRIVING HELD
BENEFIT TO TIRES.
Proving Grounds Reveal
Speed Chief Cause of
Excessive Wear.

The average driver pays so per cent
more than is necessary for his tires
Hard drivers pay a 100 per cent pre-
MUM for their tires
This is Just another way of saying
that a good driver can get twice as
much service from set Of tires as
the sort of operator who rides the
brakes and squeals around curves
Skillful drivers average so per cent
better tire mileage than those who are
medium in their handling Of cars
These facts, and many others equally
helpful to the man who wants to get
more miles per tire, have recently been
made available following extensive sur
veys.
Since tire wear Is directly related to
tire security 1t is reasonable to add
that because Of the wide variation in
driver ability some motorists enjoy
twice the safety as do their contem-
poraries on the streets and highways.
Locality Counts.
One OF the Illuminating facts de-
veloped by recent surveys is the dis
covery that your tires also wear ac-
cording to the locality in which you
drive. Tires have hard going in Pitts
burgh. New York, contrary to gen.
eral opinion, comes fourth on the list
OF best tire mileage in a group OF 10
representative cities. Detroit stands at
the top of the list. If you motor in
the motor capital you are quite apt to
obtain 81 per cent better tire mileage
than if you lived in Pittsburgh.
Hills make a difference. A group
of 121 cars in Pittsburgh showed an
average tire mileage of only 11,272.
n 1odo1nhio MI
hilly suburbs, the average of 90 cars
showed only little better mileage, at
1884. San Francisco seems to tell
the same story, with its 110 cars show
ing per tire life of only 12,471 miles.
In New York the mileage jumped to
1857. Dallas showed 1921. Chi
cago ran the mileage up to 1920,
while Detroit offered the record of
1874.
AL makes Of tires and cars were used
III this particular analysis. Mileages are
averages and do not reveal the more
Interesting fact that some Of the own
ers whose cars were checked obtained
twice as much tire service as others
This wide difference Is particularly
striking in the case of Boston, where
80 cars Of the same make and model,
carrying the same make Of tires, were
carefully checked.
Habits Are Figured.
Here only the drivers and their hab-
its figured, discounting an occasional
case of faulty brake adjustment or
front wheel misalignment Five Of the
drivers had to turn in their tires some
where between 1900 and 9,400 miles
Seven of them obtained mileages of be-
tween IL 800 and 1900. Another seven
increased this to a range Of 14,300 to
$1,000 mii-c Obviously no tire Is any
better than the man at the wheel.
Six Of the drivers considered were able
to obtain from 16.100 to 1900 miles
from their tires. The five best obtained
eral conclusion is that, aside from un-
wise use of the brakes and the difference
in geographic location, the chief source
of wear lies in excessive speed. This is
clearly demonstrated on the proving
grounds of several of the carmakers,
where tires often give but one-fifth as
much mileage as can be obtained by the
average owner
Grouping the above Boston returns, it
will be seen that the 10 hardest drivers
averaged 10,773 miles with their tires,
while the 10 medium grade drivers aver
aged 14,985 miles. The 10 best showed
the enviable mileage Of 20,231. Thus, if
your tires seem to be wearing out un-
usually fast. it would be we'll to check
up on your driving. 1t. too. may need re-
treading
Excessive Braking Needed.
Excessive speeds usually call for ex-
cessive braking. The average driver
does not realize how much he Furnishes
his tires going around curves too fast
because. with the motor buzzing vigor-
ously, he has less opportunity to hear
the tires squeal. While free wheeling
has resulted in excessive tire wear
through unwise coasting, and thus ex-
cessive use Of brakes, it has in many
instances helped drivers to realize that
they have been going around cures too
fast.
Few drivers realize that to maintain
higher speeds there Is increased need
for crater horsepower to be exerted by
the rear tires against the surface of the
road. At 80 mile an hour, for instance,
even medium sized car has to trans
NIT 55.2-horsepower draw between
tires and road. At 80 mile an hour this
Is only 81 horsepower Even at 40 miles
per hour the horsepower increase over
speed Of 80 is nearly 100 per cent.
Check your driving If you want to
cut tire costs. It's largely up to you
The time to retire depends largely on
how skillfully you re-learn.
(Copyriaht 1o3a)