Forest City press. (Forest City, Potter County, D.T. [S.D.]) 1883-19??, 1913-05-23
Gear CHANGING, ART
that REQUIRES STUDY
Care Is Required to Attain
Quietness and Is One of the
Fine Points.

40 AS GASoSOA COlk.
fronting the average amateur driver
b that Of gea changing. One may
be possessed of ample> theoretical
knowledge of motors. and of an en-
tirely adequate practical ability to
keep a a in good running order, and
yet be classed by ones friends as a
bad driver simply through inability to
Country Life. There are many men
who may claim an accurate judgment
OF speed Inc distance, a delicate touch
on ac~celerator n steering wheel and
the ability to anticipate and correct
side-slip. but who are yet rough and
unpleasant drivers through unskillful
handling of the gear lever.
1T is frequently said that on some
particular car it is difficult to change
speed. and In the case of q few old
machines there may possibly be some
oun for the statement; but in the
vast majority of cases the fault lies
either in the adjustment of clutch and
clutch stop or in the hands of the
driver. Whichever Of these latter ex-
~pianatlons be the true one, the remedy
lies in a thorough understanding IF
what happens to the car mechanism
When a change of speed is effected.
1t is common knowledge that for
pc turning faster when on a low gear
than on the next higher one. A fact
that Is not so generally realized is that,
Tor a quiet change Of gear, the driven
Of the clutch must be revolt
wing at exactly the same speed as if
n gear to be engaged were already
IN mesh. Suppose, for example. that a
car Is travelling at is miles per hour,
that the third speed is engaged and
mat 1T is desired to engage the fourth
speed. 1t may further be assumed
mat the gear ratios are lei that on
top gear the engine. must turn at 800
revolutions per minute to drive the
a at 10 miles per hour, also that. to
httaln the same speed on third gear,
the engine must be turning at 1920
revolutions per minute. We will as
sume that the operation OF changing
gear Is carried out quickly. SO that
snere Is no appreciable variation from
car. The third speed IL engaged, the
engine M clutch shaft are running at
LOO revolutions per minute and the
driver Is about to change to fourth
gear. First he disengages his clutch;
II ne releases the acceierator at the
. same Tune. as he should do, the engine
VIII slow up. and with 1t the driving
part OF the clutch. The point that
most people do not realize is that the
urlVen part OF the clutch is still rota-
ting at exactly the same speed. 1900
revolution per minute: the only diff
ference is that the car is driving the
clutch instead Of the clutch driving the
car. The next step is to slip the gear
.ever TO neutral" n it is not until
This is done that the clutch shaft will
begin to slow up.
we nave already seen that, for Is
mics per hour on top speed. the engine.
n consequently the clutch. must he
turning at 500 revolutions per minute
Clearly. then, for a quiet change, the
operator must wait with his lever In
neutral until experience tells him that
the clutch has had time to slow down
from LOO revolutions per minute to
SOO revolutions per minute: the lever
Is then moved noiselessly to top speed.
and the clutch pedal re-engaged. The
reason Tor many noisy changes of speed
Is tnat drivers, knowing a certain in
terval must elapse 10 allow the driven
clutch member to slow down., Judge this
interval from the moment Of disengag-
ing the clutch. This, of course, Is quite
wrong; as just explained. the driven
portion of the clutch goes on running
at exactly the same pace until the gear
lever is brought to neutral the
Interval found by experience to be
necessary before the top speed can be
ment of coming into neutral, not with
reference to disengaging the clutch. In
practice, Of course, the problem is
slightly complicated by the fact that
the a will slowMp to a small extent
while the change is being effected. In
other words, 1t may have dropped from
Is to IA miles per hour by the time the
fourth speed is engaged; consequently.
the driven member Of the clutch will
have to slow down to a little under
800 revolutions per minute to effect a
quiet change.
The actual time taken varies with
every car. II the clutch be heavy 1t
will fol o a limo t{rno RI C1nu, n nrd
a very p%erceptible pause viii be re-
quired in passing from third to top
speed. On the other hand. q YER light
clutch, or the use Of very thick lubri-
cant in the gear box. may cause the
clutch to slow up very rapidly, SO that
through from n speed to the other to
effect a quiet change. The adjustment
of the clutch stop further complexities
matters. II 1t be set up too tight, so
1t begins to hold the driven menu
Der Of the clutch before it IL fully dis
engaged from the driving member. 1t
may be stopped * suddenly that a
quiet change is impossible. even IL the
fever be snatched through from n
gear to the other as rapidly az possible.
The clutch stop should be set so that
there is an ample period between the
freeing Of the clutch from he engine
and the commencement OF enga9ement
clutch properly under control. II. on
slightly depressing the pedal. he finds
the interval between the gears. for a.
quiet change. 10 unduly long, he can
correct 1t by depressing the pedal to
a greater extent. thus slowing the
driven portion Of the clutch by aid OF
the clutch stop. Exactly b same
principles apply / n changing from
"frst' to SECOND" or 'second" to
third" except that in the latter case
the lever usually has to pass through
the gate. This occupies a little long
er. SO that the clutch has more time