Evening star., 1923-03-11
NEW FIELD OPENED
BY OVERSIZE TIRE
Small Diameter Wheel Used
in Successful Chicago
Experiments.
OPERATION COSTS CUT
"Unsprung Weight" Decreased.
Riding Qualities Declared
Improved.

CHICAGO, ILL.,. March "A new de-
velopment appears In the automotIve
industry in the small diameter wheel
with the large oversize tire, having,
its sponsors claim, many advantages
over the present sizes of pneumatic
tires. II.
1t was penetrated by the Yellow Cab
Manufacturing Company Of this city,
who have given It a thorough try
out in their testing laboratory, the
Yellow Cab Company of Chicago,
which operates more than 1900 cabs.
Cost Per Mile Basis.
The yellow cab Is built and operated
on a. cost per mile basis that is not
industry. The company's fixed policy
Is low cost of operation to give the
public low rates of fare. It is now
announced that yellow cabs can be
the average citizen can operate
touring car.
1t was with this in view that two
years ago the company started ex-
perimenting with the small diameter
wheel and the large oversize tire.
Today yellow cabs going to the large
municipalities, it is reported. are
equipped with n 29-inch wheel, either
DiSteel or Budd type, with either a
29x41a Firestone or Goodyear tire or
panies, it Is said, now manufacture
these sizes.
Testing Other Sizes.
In addition to these two sizes, the
above tire companies are conducting
experiments with other sizes Of big
oversize tires. Some of the large
n a NJ - ~ n fa ~,
Quoting experiments. and 1t Is said
that some time during 1929 the small
wheel and big tire will come into
general use among the prominent
passenger car manufacturers. On a
2s-inch rim the following tire size
will fit. osx4h inches. 3ox5 inches,
32x6 inches and 34x7 inches. Although
| Firestone and Goodyear are the only
tcompanies known to the Yellow Cab
organization who are going after
this oversize tire business strong, 1t
| is reported on good authority that
! all the big manufacturers will hit for
this advancement IN tire manufactur-
ing.
Riding Qualities Better.
Decreasing the wheel size and in
creasing the cross-section diameter
of the tire decreases "unsprung
weight" The improved riding quail
ties, it fs claimed, are so marked
| that other improvements. soon to be
announced by the Yellow Cab eng1-
the cabs are sprtngless.. The present
development marks the passing. 1t is
claimed, of shock absorbers, rebound
checks and similar devices which
have come into existence in an at
| tempt to prolong the life OF an auto
Portable.
M Ioaf Euernr
| With the new type tire there is no
lost energy; every explosion is trans
lated into travel. BY the same token
there Is less wear and tear on the
tires. With the large new oversize
tires the car, It Is reported, literally
floats along on cushion Of air The
resiliency Is SO perfect that all road
Inequalities are smoothed out by the
tires themselves. Travel over rutty
terrors, while the danger Of skidding
even without chains, Is practically
nullified. An additional advantage is
! the ease in which sand and mud can
be negotiated.
! Air Pressure Less.
| In the tire size as created the air
pressure is less, the life 10 longer and
the general advantages SO many that
lit Is reported. this development IL one
Of the many Of a sensational charac-
/, ter that will be announced by the
yellow Cab Manufacturing Company
who have and are conducting tests
that ara attracting the attention OF
the entire automotive world.
I A 34x7 tire on a 2sx4h rim weighs
only 6s pounds, including the wheel
tire. tube and flap. In experiments
Iconducted by the Yellow Cab in Chi
1 caRo 1t is reported that 29x4h Inch
tires have thus far given $4,000 miles
Of service and are still good for many
more, and it Is further pointed out
this is regular service for these tires
line consumption in the oversize tires
has been increased from three to five
miles per gallon, not only In tests with
yellow cabs, but also with passenger
cars.