Yamaha yz450f 2012 Service Manual

7-6
THROTTLE POSITION SENSOR SYSTEM
THROTTLE POSITION SENSOR SYSTEM
INSPECTION STEPS
If the throttle position sensor will not operate, use the following inspection steps.
*marked: Refer to "IGNITION SYSTEM" section.
Use the following special tools in this inspection.
Check entire ignition system for connection. No good → Repair or replace.
OK ↓
Check throttle position sensor. No good → Replace.
OK ↓
*Check AC magneto. No good → Replace.
OK ↓
Check ECU. (Throttle position sensor input volt-
age)
No good →
Replace.
Model 88 Multimeter with tacometer:
YU-A1927
Digital circuit tester:
90890-03174
Test harness-speed sensor (3P):
YU-03208/90890-03208

Yamaha yz450f 2012 Specifications

General

Bore x Stroke	97.0mm x 60.8mm
Compression Ratio	12.5:1
Fuel Delivery	Fuel Injection
Transmission	5-speed
Final Drive	Chain
Tires Front	80/100-21
Tires Rear	120/80-19
Wheelbase	58.7 in
Trail	4.6 in
Fuel Capacity	1.6 gal
Wet Weight	245 lb
Engine Type	Liquid-cooled, 4-stroke, DOHC, 4-valve
Ignition	TCI
Suspension Front	Telescopic fork, 12.2 in travel
Suspension Rear	Swingarm, 12.4 in travel
Brakes Front	Hydraulic single disc brake, 250mm
Brakes Rear	Single disc, 245 mm