The Washington times. [volume] (Washington [D.C.]) 1902-1939, 1915-12-11
Weight and Distribution Are
Chief Among Many Other
Factors.
PRESSURE GAUGE NECESSARY
Storage Deterioration May Be
Avoided by Excluding Light
and Heat.

Tire USAGE. with suggestions for re-
ducing expense, IL the theme OF tbif
series of eight articles by j. j. haas
manager Of the Washington branch 81
the Flrestone Tire and Rubber Com
pany.
This is the fourth In the series. Sue
eessive articles will appear In tho auto
mobile section Of The Times each sat
urday.
No. Limitation and Storage.
By ]. J. HAAS.
inf ATION-The style OF car con-
struction. power. speed. road conditions,
the expert or careless driver and as
pecially the weight and its distribution
play an import nnt rart with the strains
to which the tires will be subjected
consequently. q fxcd rule for imitation
would, in view of these thingS. produce
different results.
Ordinarily. the tires on front wheels
should be inflated between fifteen and
eighteen pounds per inch Of tire sec
ton apd tho rear tires fifteen to twenty
pounds per inch OF tire section.
Resiliency OF the tires II primarily
governed by the construction and quail
ity but Is largely influenced by the iR-
hatlen and weight carried. Naturally a
four-inch tire inflated to seventy hounds
air pressure and carving 500 pounds
size OF tire with the same imitation and
carry TO pounds weight. The heavier
weight causes moro detection Of the
tires on the ground and inoIeaaes the
to the comfort of the ride. Increasing
tho detection or 1attening OF tires
either by extra weight or reducing tbs
air pressure; causes more OF tte EieTa'
than by the springs Of the car.
Effect of Flattening.
When soft. the tire runs asainst 3
wave in tho tread rubber which vii
from excessive stretching and heating
pull away and separate from carcass Of
body. The heat from increased &C
ton in the side walls Of under Undated
tires softens the rubber cement or ad
hosivenesS between the fabric layers-de-
vulcaniZation takes place, 20 some eX-
gree. Too much detection OF tire also
means an irregular tension Of one layer
of fabric In relation to another-theS
pull apart chafe. and later. when
striking a stone. rough place or rut, 4
blowout may occur,
There seems TO be an Impression Of
danger from blowouts due to expansion
especially during the hot weather
ter OF tact. II iS not il pro dor 10 the
increase in temperature. for example,
II the temperature OF the air In q tire
increases from sixty to eighty degrees
II does not follow that the air pressura
Per square inch increases from sixty ia
eighty pounds. II actually means an
increase Of three pounds pressure psi
square inch: that is, the pressure In
creRses from sixty to slXty-three pounds
New tires stretch sliGhtly after In
service . while, and inner tubes. .wher
heated to 8 certain degrea. are slightlS
pcrmeable TO nitrogen, and occAsioua
imitation IL, therefore, advisable. De-
terioFating effects OF stale air can be
avoided by filling the tires with fresh
supply Of air. at least two or three
times a year.
Use Pressure Guage.
The tires should not be inflated with
the exhaust from the engine. a. oil and
certain gases are destructive to rubber
this docs not have reference TO pumps
operated by power from the engine.
Dent make the mistake of guessing al
the imitation from appearances or by
striking the tires with Q hammer: use
pressure gauge at least every week
tires sometlmes appear to round pretty
well. but, when tested with a gauge. il
may be found that the pressure IL en-
tlrely too low to insure the best results
We believe the most satisfactory infla,
tor method Is TO pump up the tires IN
ae cordaDce with formula. Then, II
necessary, reduce the pressure slightly
until they do not cause excessive Vbra.
ton to the car and traction slippaGe OF
the rear wheels. Make a record Of tho
pounds pressure At this point, and, II
always maintained, the greatest cf-
hcIeney, from tires and car will be en-
joyed.
Deterioration, contrary to the general
impression, Is not necessarily a result
OF age, but is largely Influenced by the
conditions TRn6ap Nuhfrh Ill,
in stock.
Effect of Light.
When exposed to the light and sun,
especially to the hot summer sun. the
rubber will dry out, harden, and the
efficiency and life of the tire will DO im-
paired. As = protection from light,