The Portland daily press., 1896-05-23

| three quarters OF h Ano"
plate is a segment of circle Inc ne"
fire can be adjusted to wheel OF any
size. It may be used In either a single
or a double tube rubber tire. In the
case of a double tube tire the steel shield
Ga nlaced between the two tubes; in that
Of a single tube tire, inside the rubber
tube Mr.. Dean, however, intends to
manufacture tire of his own. This
will be single tube rubber tire, and
the shield will occupy that space between
the layers of rubber usually taken up By
one of the layers of canvas.
The use of leather for pneumatic tires
is attracting attention in the West A
the outer cass of which is manufactured
from specially prepared leather, which
contains an endless tube of rubber, firm
" cemented ON the underside to the
leather. This makes practically single
tube leather tire. The manufacturers
claim for this tire that it is especially
adapted fol- use on rocky or flinty roads,
and that it will stand an unusual amount
of wear and tear without any danger of
puncture. Another quality claimed for
these tires is that they will not slip on
muddy pavements and are not affected by
heat or cold.
In the average bicycle, says the bicycle
editor Of the New York Evening Post,
there are about 14O steel balls. These
are generally distribu ted as follows:
Front wheel, 16; back wheel. IS; crank
shaft, %; pedals, 90 each; front steering
head, 40 These are of different sizes,
those used in the front wheel generally
the back; the balls in the pedals are
about 1-S Of an inch in diameter. With
such a number of points at which there
may be friction it will readily be seen
that even the smallest imperfection
would have very material effect upon
the running qualities of the wheel. For
/ this reason IN ore care Is taken in their
manufacture than in that Of any other
part of the wheel. The perfect bicycle
hall must be absolutely exact as to gauge.
1t must be highly polished and it must
be so hard that even an emery wheel will
have little effect upon It, The other
parts of the bearings are also very i'm
portant, but perfection in them is not SO
difficult to secure as in the balls. The
ball cups on nearly, if not quite all ma
chimes, ara forced into their places in the
wheel, pedal or bracket by hydraulic
pressure, and are practically as solid as
if they were brazed or welded to the part
in which they fit. The cones which press
| the balls into their places in the cups are
removable, and in case of any iInperfec-
sions can be easily and cheaply replaced.
Perfect bearings should be the last things
to wear ont in wheel, and years of use
should only be evidenced by bright
streak in the ball races showing where
the balls had run.
Question woman rider about the gear
of her wheel says. Harper's Bazaar, and
in a majority Of cases you will find that
she has no idea whether it is high or
low. Indeed, it is doubtful if she even
knows the meaning of the word, or has
considered the matter worth her atten-
ton. 1t is not quite fair to charge all
the Ignorance to women, for there are
men who ride every dey and know no
more about it, but it Is with women that
this column is concerned. And the gear
is one Of the important things to be
looked after in the wheels running quail
: ities. Each person must decide for her.
self how high or how low 1t should be
for her comfort. The word refers always
to thu diameter of the rear wheel-that
is, 60-gear means that the machine ia
arr anged to nave the rear wheel rsvolve
. | rs til ough it were go inches in diameter.
This is accomplished by means of the
chain turning over a large sproeket in the
. front and a small one in the rear. The
, | varying proportions Of the numbers Of
teeth on the two sprockets produce the
variations in gear. For 28-inoh wheels,
which are now almost universally used.
the gear 90 will be obtained if there are
Is teeth on the front and seven on the
rear spr ocket. Thirteen and six and 19
and will also approximate 60. men,
tiou go because that or about SO, is the
favorite gear this season. Formerly
women's wheels were Dever geared higher
than Sc, unless by special order. The
higher the gear the fewer revolutions of
the pedals are nesded, but Of course pro-
portionately more strength must be put
into each push. In going at considerable
sp eed the motion is more graceful where
5 is pretty stiff work with high gear, and
it is always best not to go to either one
extreme OF the other. 10 find the gear
of a bicycle when you do not know it,
multiply the diameter OF the rear wheel
by the number of teeth on the front
sprooket, and divide the result by the
} number of teeth on the rear sprocket.
A rider who displays sufficient in.
; genuity to have his bell on the inside OF
the handle bar instead Of on top or IL
: front, says the New York Recorder. Is
. indeed rarity. Yet the sole cause Of
I bells becoming cracked and out of order
Q is the great amount of knocking they re-
3 ceive. Every time the wheel falls or is
let rest against anything hard 1t is gen
! orally the bell side of the handle ba,
: which is turned In, and the bell soor
. loses its tone and loudness. This would
@ be obviatsd If the bell was on the inside,
8 as the inward sweep of the handle bal
would protect it. Another advantage il
8 that the bell could be placed on the right
f hand side, and be rung by simple
g downward pressure of the thumb.