|
|
|
|
|
For 2007, the bike that started the four-stroke revolution benefits from significant chassis and engine refinements that ensure the five-titanium-valved YZ450F remains at the head of the open-class pack.
|
|
|
|
|
|
Modifications to the light and strong aluminum frame and suspension mean light, precise, confident handling at any speed.
|
|
|
|
|
|
Five-speed gearbox provides maximum flexibility and the right gear for a wide range of riding environments.
|
|
|
|
|
|
Ready to race straight out of the crate - with a ProTaper aluminum handlebar in adjustable clamps, titanium shock spring, ti footpegs, gripper seat, etc.
|
|
|
|
|
|
|
|
Replacing the upper cast triple clamp with a light and strong forging, slightly reducing steering head rigidity, and the use of lighter outer fork tubes; lighter wheel rims and light wave-type brake rotors add up to super-accurate, super-responsive steering.
|
|
|
|
|
|
Increasing the length of the rear shock by 1.5 mm further sharpens handling. Replacing steel damping adjusters with aluminum ones removes even more weight from the four-way adjustable, titanium-sprung rear suspension unit.
|
|
|
|
|
|
A more rigid clutch pressure plate helps put power to the ground and dissipates heat more efficiently, especially during partial-clutch operation. Shorter lever stroke with 12-percent reduced effort means instant response.
|
|
|
|
|
|
New, titanium exhaust pipe fattens low- and mid-range power while simultaneously adhering to 2007 AMA noise regulations.
|
|
|
|
|
|
This year's ProTaper aluminum handlebar bend raises the grips 8 mm for an expanded cockpit. Forged bar clamps reduce weight for superior handling.
|
|
|
|
|
|
|
|
449 cc five-valve DOHC liquid-cooled engine is super-powerful yet tractable.
|
|
|
|
|
|
39 mm Keihin FCR flat-slide carburetor with throttle position sensor (TPS) and leak jet delivers precise fuel/air mixture and instant throttle response.
|
|
|
|
|
|
Revised CDI ignition keeps that amazingly broad and deep powerband hard-hitting, yet controllable.
|
|
|
|
|
|
Lightweight, titanium valves and load-reduced springs minimize reciprocating mass for fast-revving, hard-hitting power delivery across the rev range.
|
|
|
|
|
|
Additional weight-saving engine features include: small-design cam chain tensioner and oil pump, aluminum oil hose, all-titanium exhaust header, flange, bracket and heat shield and light CDI ignition unit.
|
|
|
|
|
|
Primary kickstarting with automatic decompression and convenient handlebar-mounted hot start lever ensures easy restarts.
|
|
|
|
|
|
Kick pinion gear is separate from the primary driven gear for smoother clutch engagement.
|
|
|
|
|
|
Large-capacity radiator is reinforced for greater strength.
|
|
|
|
|
|
|
|
Aluminum frame uses a mix of alloy casting, forgings and extrusions to produce a tuned-flex frame that makes the YZ the finest handling motocross bike ever.
|
|
|
|
|
|
Speed-Sensitive System 48 mm Kayaba fork places transfer control valves (TCV) above the fork springs, so that damping force is controlled by piston speed; eliminating mid-stroke damping force changes provides a smoother, more precise ride.
|
|
|
|
|
|
Titanium-sprung four-way adjustable rear shock with Kashina-coated internals reduces friction for fantastic compliance and great handling.
|
|
|
|
|
|
More weight savings come via two-piece (part aluminum, part plastic) engine protector plates and thin-walled engine guard construction.
|
|
|
|
|
|
Removable aluminum rear subframe constructed of square-section tubing for light weight and easy maintenance - lighter fasteners for 2007 enhance weight distribution and handling.
|
|
|
|
|
|
Lightweight front wheel hub for reduced unsprung weight and increased durability.
|
|
|
|
|
|
Premium Dunlop knobbies provide unbeatable, competition-spec traction and great wear.
|
|
|
|
|
|
Lightweight 21-inch front and 19-inch rear Excel rims are exceptionally durable and reduce unsprung weight.
|
|
|
|
|
|
|
|
"Gripper" style seat cover gives excellent feel and control, and the seat is lighter for 2007.
|
|
|
|
|
|
Wide, cleated, folding titanium footpegs are light, strong, and provide excellent comfort, grip and ground clearance.
|
|
|
|
|
|
Works-style clutch lever features oversize barrel adjuster for easy, on-the-fly adjustability of lever/cable play.
|
|
|
|
|
|
Cleated rear brake lever and folding shift lever tip offer superb grip and excellent durability.
|
|
|
|
|
|
Repackable exhaust silencer.
|
|
|
|
|
|
Durable, comfortable handlebar grips.
|
|
|
|
|
|
Stainless steel clutch cable for longer life.
|
|
|
|
|
|
|
|
|
|
Main Jet: #160
|
|
|
|
|
|
Main Air Jet: #200
|
|
|
|
|
|
Jet Needle: NFLR-4
|
|
|
|
|
|
Pilot Air Jet 1: #100
|
|
|
|
|
|
Pilot Outlet: 0.9
|
|
|
|
|
|
Pilot Jet: #45
|
|
|
|
|
|
Primary Reduction Ratio: 61/23 (2.652)
|
|
|
|
|
|
Secondary Reduction Ratio: 49/13 (3.769)
|
|
|
|
|
|
Gear Ratio - 1st Gear: 27/14 (1.929)
|
|
|
|
|
|
Gear Ratio - 2nd Gear: 23/15 (1.533)
|
|
|
|
|
|
Gear Ratio - 3rd Gear: 23/18 (1.278)
|
|
|
|
|
|
Gear Ratio - 4th Gear: 24/22 (1.091)
|
|
|
|
|
|
Gear Ratio - 5th Gear: 20/21 (0.952)
|
|
|
|
125.jpg)
Specs, Quotes, Overview
Standard Features
