2004 YZ450F


2002 YZ426F


Engine


2004 YZ450F


2002 YZ426F

Bore x Stroke

95 x 63.4mm

95 x 60.1mm

Carburetion

39mm Keihin FCR flat-slide w/throttle position sensor

39mm Keihin FCR flat-slide w/throttle position sensor

Compression Ratio

12.5:1

12.5:1

Final Drive

#520 Chain

#520 Chain

Ignition

Digital CDI

Digital CDI

Transmission

4-speed w/multi-plate wet clutch

5-speed w/multi-plate wet clutch

Type

449cc, liquid-cooled, 5-valve, DOHC, 4-stroke w/titanium valves

426cc, liquid-cooled, 5-valve, DOHC, 4-stroke w/titanium valves


Chassis


2004 YZ450F


2002 YZ426F

Brakes/Front

250mm Floating Disc

250mm Floating Disc

Brakes/Rear

245mm Disc

245mm Disc

Suspension/Front

48mm Kayaba inverted telescopic fork w/adjustable compression and rebound damping; 11.8" travel

46mm Kayaba inverted telescopic fork w/adjustable compression and rebound damping; 11.8" travel

Suspension/Rear

Kayaba single shock w/adjustable preload, compression and rebound damping & separate hi/lo-speed compression adjuster; 12.4" travel

Fully adjustable Kayaba single shock, 12.4" travel; separate hi/lo speed compression adjustment

Tires/Front

80/100-21 Dunlop

80/100-21 Dunlop

Tires/Rear

110/90-19 Dunlop

110/90-19 Dunlop


Dimensions


2004 YZ450F


2002 YZ426F

Dry Weight

222 Lbs.

231 Lbs.

Fuel Capacity

1.8 Gallons

2.1 Gallons

Ground Clearance

14.6"

14.7"

Height

51.3"

51.3"

Length

85.5"

85.5"

Rake (Caster Angle)

27.2

Spec Not Available

Seat Height

39.2"

39.3"

Trail

4.7"

Spec Not Available

Wheelbase

58.5"

58.7"

Width

32.6"

32.6"


Other


2004 YZ450F


2002 YZ426F

Color

Team Yamaha Blue/White

Team Yamaha Blue/White

Gear Ratio - 1st Gear

27/14 (1.929)

24/13 (1.846)

Gear Ratio - 2nd Gear

25/16 (1.563)

23/15 (1.533)

Gear Ratio - 3rd Gear

23/18 (1.278)

23/18 (1.278)

Gear Ratio - 4th Gear

21/20 (1.050)

24/22 (1.091)

Gear Ratio - 5th Gear

Not Applicable

20/21 (0.952)

Gear Ratio - 6th Gear

Not Applicable

Not Applicable

Jet Needle

NCVQ-4

0BEJP-4

Main Air Jet

#200

#200

Main Jet

#165

#162

Needle Jet

(2.9mm ID)

2.9mm (I.D.)

Pilot Air Jet 1

#100

#100

Pilot Jet

#42

#42

Pilot Outlet

0.9

0.9

Primary Reduction Ratio

62/22 (2.818)

62/21 (2.952)

Secondary Reduction Ratio

48/14 (3.429)

49/14 (3.500)

Warranty

30 Day (Limited Factory Warranty)

30 Day (Limited Factory Warranty)

MSRP

$6,299* Available from August 2003

$5,999*




YM ('00) to YN ('01) Clutch Update Parts:

5JG-16321-00-00 PLATE, FRICTION
5JG-16383-00-00 SPRING, CLUTCH BOSS
5JG-16384-00-00 PLATE, SEAT
93511-32027-00 BEARING, BALL (PUSH ROD ASSY.)
5JG-16356-00-00 ROD, PUSH 1
5JG-16357-10-00 ROD, PUSH 2
5JG-15453-00-00 GASKET, CLUTCH COVER