Yamaha MTN1000 2016 User Manual

AIR INDUCTION SYSTEM
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EAS30488
CHECKING THE AIR INDUCTION SYSTEM
Air injection
The air induction system burns unburned ex-
haust gases by injecting fresh air (secondary air)
into the exhaust port, reducing the emission of
hydrocarbons. When there is negative pressure
at the exhaust port, the reed valve opens, allow-
ing secondary air to flow into the exhaust port.
The required temperature for burning the un-
burned exhaust gases is approximately 600 to
700 C (1112 to 1292 F).
Air cut-off valve
The air cut-off valve is controlled by the signals
from the ECU in accordance with the combus-
tion conditions. Ordinarily, the air cut-off valve
opens to allow the air to flow during idle and
closes to cut-off the flow when the vehicle is be-
ing driven. However, if the coolant temperature
is below the specified value, the air cut-off valve
remains open and allows the air to flow into the
exhaust pipe until the temperature becomes
higher than the specified value.
1. Check:
• Hoses
Loose connections  Connect properly.
Cracks/damage  Replace.
2. Check:
• Reed valve
• Reed valve stopper
• Reed valve seat
Cracks/damage  Replace the reed valve
assembly.
3. Measure:
• Reed valve bending limit “a”
Out of specification  Replace the reed
valve assembly.
A. From the air filter case
B. To the cylinder head
Reed valve bending limit
0.4 mm (0.02 in)

Yamaha MTN1000 2016 Specifications

General

Model	MTN1000
Year	2016
Manufacturer	Yamaha
Engine Displacement	998cc
Bore x Stroke	79.0 mm x 50.9 mm
Fuel System	Fuel Injection
Transmission	6-speed
Final Drive	Chain
Front Tire	120/70 ZR17
Rear Tire	190/55 ZR17
Overall Length	2095 mm
Overall Width	800 mm
Overall Height	1110 mm
Seat Height	825 mm
Wheelbase	1400 mm
Ground Clearance	130 mm
Category	Naked
Engine Type	Liquid-cooled, 4-stroke, DOHC, 4-valve
Ignition	TCI
Front Suspension	Telescopic fork
Rear Suspension	Swingarm
Front Brake	Dual hydraulic disc
Rear Brake	220mm hydraulic disc
Fuel Capacity	17L