Honda C65 - Function of the Respective Components; Main Jet; Air Jet; Needle Jet

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Main Jet
Figure 3- 96 . Main jet
Figure 3- 97.
Air j et
Figure 3- 98 . Need le jet
3. ENGINE
5.
a .
However, depending upon its usage, 11 ma y result
in
engine stalling or flo od ing. To counter this situa-
tio n, a relief valve @ is in corpor ated in the choke
v alve @ to open or closes at a preset suction pres-
sure,
to produce a p roper fuel air mixt ure for cold
w eathe r starting. It is there fo re possible to close the
ch
oke valve completely dur ing warm-up driving and
en fully open the val ve after war m-up. (Fig. 3- 95)
10 OF THE RESPECTIVE
COMPONENTS
o i je
h e_ -·cs · ~e =uel flow during full th rot tle con-
d i"ion · oo s:::eec ·o provid e a pro per fu el mixtu re .
Not o ly does ·. =.;"cion a to p speed but also is
effec tiv e o a ce · a·~ degr ee oi inter mediate speed.
The l
arge r he ·e size mumber, g reater will be
the fuel flow a ·o "cfng a rich er fuel mi xture .
(Fig.
3-96 )
b. Air j et
During full throttle o pe n ing, the fuel mixture at
high engine
sp ee d will b ecome rich and at sl ow
engine s peed he mixture becomes leon. To prevent
such a condition, a ir is bl ed into the ma in jet . The
function of the air jet is to restrict the amount of air.
As the a ir jet is mode larger, the amount of air is
incre a se d, re su lting in a l eo n fuel mixture, h owever,
at the th rot t le open ing, a h ig h engine speed will
provide a lean mixture with a sma ller var i ation in fuel
consump
tio n be tw een h igh and l ow eng ine speed.
(Fig.
3- 97)
c. Needle jet
Du ring full o r half thr o ttle open ing , the fuel wh ic h
hod
been m ete red by the ma in jet is again ~ tered
by the n ee dl e j et . The adjustment is performe d in
c
on junc ti o n with the jet n eed le whic h is exp la in in the
fo ll ow ing section. The needle hole is mo dA exce p-
ti ona lly accu rat e. (Fig. 3- 98)