The Birmingham age-herald. [volume] (Birmingham, Ala.) 1902-1950, 1923-04-08
RUBBER COMPANY
EXPERIMENTS D n
LARGE THIN TIRE
Expected To Increase Riding
Comfort-Sxperiments BY
U. S. Rubber Company

Some experimental work with au-
tomobile tires so large. and thin that
they have been described as balloon
tires" is being done by the United
States Tire company The results OF
! these experiments seem to indicate
important changes in the future de-
velopment of pneumatic tires.
The first pneumatic tire used on
bicycles were called balloon tires
They were so much larger than the
solid or cushion tires in vogue up to
that time that their appearance ocea-
stoned considerable humorous COM
ment, but this was soon forgotten
when the great advantages of the
new tire came to be understood.
The experimental work now under
way may again make this appella-
ton popular.
In the experiments now being car
ried on by the United States Tire
company, cord tires large in cross
section and having very thin car
casses have been substituted for the
present conventional sizes with a
view to providing greater cushion
ing for passenger cars
These large, thin tires. under equal
load conditions, can be operated with
much lower initiation pressures than
the smaller ones, and thereby in
crease the ease of riding to a degree
example, "a by four-ply cord tires
have been tested on a car normally
equipped with SO by eight ply
cords. At an initiation pressure of 20
pounds per square inch these bal
loon" tires will roll over a two by
four lying on the road without any
appreciate jolt, and do 1t at low
speeds.
The SO by tires will, on the other
/ !, q q
road surface without rolling over 1t
unless the car is travelling very fast,
and then a severe jolt VIII be eXpe-
rienced.
The substitution of these super
tires for those of conventional sizes
is accomplished without effect on the
driving characteristics of the car or
on it's road clearance. Their in
creased sectional dimensions are OBJ
tanned by using smaller rim
present popular 23-inch-so that the
outside diameter is about the same.
The 80 by s. in this thin carcass type,
replaces the 81 by 4; the 81 by 6
replaces the 80 by Az, and the 81 by
Z the SO by ). These tires should not
be confused with the new line OF
pneumatic truck tires in these same
2O-inch rim diameter sizes. They are
comparable in outside diameter and
) inches. 6 inhces and Z inches carry
from to IL plies of cord and operate
I at initiation pressure up to loO
pounds per square inch. The super
/ tires for passenger cars are not ap-
preciably heavier than the present
size tires.
These experiments represent an ex-
tension of the pneumatic principle In
a logical direction and bring the tire
much nearer the engineers ideal-a
! tire "as flexible as a soap bubble and
! as strong as steel" There is no
increase in fuel consumption nor de-
crease in ease of steering. In add
ton to their wonderful riding quail
| ties these large tires give added
braking effects and much better non
skid and tractive qualities. IN fact,
those who have ridden on them ana
also in European cars equipped with
four-wheel brakes, state that the
successful commercial development
of these big. thin tires will 'unques-
tionably render the four- wheel brake
system obsolete. and >cevent its ever
being popular in America.
In it's statement. the United states
Tire company makes it clear that the
announcement is made only as a mat
ter of interest, and that much work
has yet to be done before super tires
will be available to the public