SECTION 05 - ENGINE PREPARATION
MMC2005-001_05A.FM
05-17
Starting Device (enrichner)
Instead of a choke, the enrichner system is used
on some Mikuni carburetors. In the starter type,
fuel and air for starting the engine are metered
with entirely independent jets. The fuel metered
in the starter jet is mixed with air and is broken into
tiny particles inside the emulsion tube. The mix-
ture then flows into the plunger area, mixes again
with air coming from the air intake port for starting
and is delivered to the engine in the optimum air/
fuel ratio through the fuel discharge nozzle. The
starter is opened and closed by means of the start-
er plunger. Since the starter type is constructed so
as to utilize the negative pressure of the inlet pipe,
it is important that the throttle valve be closed
when starting the engine.
1. Plunger area
2. Emulsion tube
3. Inlet pipe
4. Needle jet
5. Float
Selection of the Aperture of Carburetor
One of the prerequisites for improving the output
is to use a carburetor with as large an aperture as
possible. However, a large aperture alone does
not necessarily improve the output. As shown in
the following illustration, it is true that a large ap-
erture improves the power output in the high
speed range. In the slow speed range, on the other
hand, the output drops. The aperture of a carbure-
tor is determined by various factors. These factors
include (1) whether the vehicle is intended for rac-
ing, (2) the design of the engine, (3) driving tech-
nique of the driver, (4) the driver’s preference, etc.
In addition, the maximum output, the maximum
torque and the minimum number of revolutions
for stable engine operation must also be taken into
account.
Size of Mikuni Carburetors
Mikuni VM-type carburetors come in various sizes,
with the main bore ranging from 10 mm (.39 in) to
44 mm (1.73 in) (in even numbers for the most
part.) The carburetor body is made of aluminum or
zinc.
A01C4EB
1
2
3
4
5
Revolutions per minute (RPM)
A01C2OA
Too large an aperture
hp
Proper aperture
Too small
an aperture
Содержание ski-doo MACH Z 1000 SDI
Страница 1: ...Mmc 2005 001 Racing FH8 Wed Sep 15 15 27 01 2004 Page 1 C M Y CM MY CY CMY K...
Страница 118: ...04 36 MMC2005 001_04A FM SECTION 04 SUSPENSION SC 3 SC 4 RAS SC IV REAR SUSPENSION 0...
Страница 124: ...04 42 MMC2005 001_04A FM SECTION 04 SUSPENSION SC 3 SC 4 RAS...
Страница 196: ...05 72 MMC2005 001_05A FM SECTION 05 ENGINE PREPARATION FUEL TANK AND FUEL PUMP All Models except SDI 2 4 3 1 A33C2VS...
Страница 289: ...SECTION 06 DRIVE SYSTEM MMC2005 001_06A FM 06 27 422 A01D3JA 417 222 562 427 A01D3KA 417 222 677...
Страница 473: ...SECTION 12 SERVICE TOOLS MMC2005 001_12A FM 12 29 N Scratch remover P N 861 774 800 APPLICATION All models...
Страница 476: ...MMC2005 001_13A FM 13 1 SECTION 13 ACCESSORIES TABLE OF CONTENTS 0 ACCESSORIES 13 02...
Страница 493: ...Mmc 2005 001 Racing FH8 Wed Sep 15 15 27 01 2004 Page 1 C M Y CM MY CY CMY K...