Idle Speed Adjustment - Yamaha V star 1100 Owner's Manual

LUBRICATION, MAINTENANCE AND TUNE-UP
33
34
35
4. Attach a portable tachometer to the No. 2 cylin-
der (front cylinder) spark plug lead following the
manufacturer's instructions.
5. Remove the plug (Figure 33) from the vacuum
fitting on each cylinder's intake manifold. On mod-
els with an AIS system, remove the AIS hose (Fig-
ure 34) from the vacuum fitting on the rear
cylinder's intake manifold.
6. Connect the vacuum lines from the vacuum
gauge to the vacuum fitting on each intake manifold
following the manufacturer's instructions. Be sure
to route the vacuum lines to the correct cylinder.
7. Attach an auxiliary fuel tank to the carburetor.
Start the engine and let it warm up.
8. With the engine running at the idle speed listed
in Table 5, check the gauge readings. The vacuum
pressure at each cylinder must be within the range
specified in Table 5.
9. If the difference between the vacuum readings in
the two cylinders is greater than 1.33 kPa, (10 mm
Hg [0.4 in. Hg]), synchronize the No. 1 carburetor
to the No. 2 carburetor by adjusting the synchroniz-
ing screw (Figure 35). Turn the screw until the vac-
uum readings in the two cylinders are equal or as
close as possible.
10. Check the idle speed. If necessary, adjust it as
described in this section.
11. Stop the engine and detach the equipment.
12. Reinstall the plug (Figure 33) onto the intake
manifold vacuum fittings. On models with an AIS
system, reconnect the AIS hose (Figure 34) to the
fitting on the rear cylinder intake manifold.

Idle Speed Adjustment

Before adjusting the idle speed, clean or replace
the air filter, test the engine compression and syn-
chronize the carburetors. Idle speed cannot be prop-
erly adjusted if these items are not within
specification. Refer to the procedures described
earlier in this chapter.
1. Remove the cylinder head cover from the rear
cylinder as described in Chapter Four.
2. Attach a portable tachometer to the No. 1 cylin-
der (the rear cylinder) spark plug lead following the
manufacturer's instructions.
3. Start the engine and warm it to normal operating
temperature.
4. Sit on the seat while the engine is idling and ad-
just your weight to remove as much weight as possi-
ble from the front wheel. Turn the front wheel from
side to side without touching the throttle grip. If the
engine speed increases when the wheel is turned,
the throttle cable may be damaged or incorrectly ad-
justed. Adjust the throttle cable as described in this
chapter.
5. Turn the throttle stop screw (Figure 36) to set
the idle speed to the specification in Table 5. When
viewed from the left side, turning the throttle stop
screw toward the rear increases idle speed; turning
it toward the front decreases idle speed.
69
3