Daily Kennebec journal. [microfilm reel] (Augusta, Me.) 1870-1975, 1897-09-13
Against the chainIess Wheel.

Rolla G. Carpenter professor of ex-
pcrimental engineering at Cornell Unit
versity. has investigated the relative
merits of the safety as compared with
the geared or chainless wheel The
conclusions he arrives at are not ia
vorable to the latter the professor
holding that no better power conveyor
than the chain can be found In 4
published letter on the subject Profess
sor Carpenter says:
1T seems safe to announce that all
of the tests indicate that no form II
gearing can possibly equal the best
chain for efficiency and durability
Some Of the results of the test may be
interesting, and it may be briefly state
that the friction with the best chain
varied from one-half to quarters
Of one per cent. and this result was not
only obtained with new chain, but
was also obtained with a chain which
had been in use on a wheel that hal
been ridden for more than 1000 miles by
rider weighing nearly 200 pounds
This would serve to show that high
grade chains can be and are made
which do not change their form by
wear an amount sufficient to affect the
friction. Tests We're made on q large
number of other chains, and the fric-
ton was found 10 vary from two to
five per cent, depending upon the con-
dition of the chain. it's method of con-
struction and details of design. The
highest friction we have found even h
the case of an old chain which did not
tit the sprocket properly, did not ex-
coed 10 per cent although / am willing
to concede that considerably higher
friction might in some instances be
found
Regarding the use of gears extern
sive Investigations have been made
from time TO time which show the
amount of power lost in friction. The
very best recorded results with spur
gearing are very nearly equal to thosc
obtained with the ordinary chain when
the gearing is in the best condition ana
working accurately in line and posi-
ton. The best kind of bevel or spiral
gears, a form which must be used in
bicycle work show about three times
the friction of the spur gears. and since
two pairs must be used on each bicycla
about four times as much friction u,
the ordinary chain will be developed
and six to eight times the friction OF
the very best chains.
There is another serious objection To
the use of gears. arising from the fact
that the least change in position of tn.
point of contact OF the gear from it,
normal will cause a great increase in
friction and in loss of power over that
stated in the preceding discussion.
This indicates that the gearing is es-
sentially untitled for a frame which
must from the very nature of its use
possess great elasticity and fiexibility. |
The chainless wheel also developed ons |
extremely bad feature, and as this 4 |
inherent in all methods of gearing t |
may perhaps be worth mentioning. |
With all the chain wheels the per-
centage of friction or loss of power
essentially constant at ali |
speeds. but with a geared or chainless
wheel the percentage of friction in
as the speed diminished. This
would make the chainless wheel very
Objectionable for climbing hills. since
at that time the speed must be slow
md all the power of the rider is needed
20 propel the wheel forward"