Essentially, as you may be aware, most rear suspension systems contain a mount for the upper end of the shock body that integrates with the frame or sub-frame of the motorcycle. In developing Valentino Rossi's race bike, Honda applied a suspension method that eliminates the connection between the top of the shock body and the motorcycle frame. Essentially, with the exception of the lower suspension linkage, the rear suspension system on the MotoGP machine, as well as the 2003 CBR600RR, is self-contained within the swingarm.

According to Honda, the system isolates the main part of the chassis, including the steering head, from jolts to the rear wheel. Here is a quote from some of Honda's press material distributed in Europe.

Based entirely on the compact system supporting the rear swingarm of the dynamic, new RC211V, the CBR600RR's unique Unit Pro-Link rear suspension system is entirely self-contained within the swingarm it supports, with no connection to the main frame, save for the lower arms providing an anchor for its newly configured Delta Link. This innovative new design totally isolates the frame and steering head from the shocks and stresses exerted on the rear wheel and suspension under spirited riding and racing extremes, and makes a significant contribution to the CBR600RR's total mass centralisation, and by extension its sharper, more responsive handling.

The damper's upper mount, previously attached to the frame's upper rear crossbar, is now held in place by a bolted-on mounting bracket installed in the upper surface of the swingarm's massive pivot section. The damper's prominent remote gas reservoir is positioned within easy reach for quick adjustments of compression and rebound damping.

Features & Benefits
Unique CBR600RR Features

Unit Pro-Link(r) rear suspension and swingarm design inspired by RC211V.
Dual Stage Fuel Injection system features two injectors per cylinder.
High-revving engine redlines at 15,000 rpm.
New-style center-up exhaust system.
Centrally located fuel tank increases mass centralization and allows more compact frame design.
New Line Beam Headlight features three-piece reflector design.
Engine/Drivetrain

All new liquid-cooled DOHC 16-valve 599cc four-stroke inline four-cylinder engine features oversquare bore and stroke of 67mm x 42.5mm.
High-revving engine has 15,000-rpm redline (CBR600F4i redlines at 14,200), wider powerband and more over-rev than CBR600F4i.
New engine is more compact-engine length is now 236mm vs. 266mm-which helps move the rider forward 70mm.
New iridium-tip spark plugs improve fuel combustion and performance.
Dual Stage Fuel Injection (DSFI) system features two injectors per cylinder-one upper and one lower-controlled by an ECU that senses rpm and throttle opening. Lower injector enhances rideability while upper injector improves top-end horsepower. At lower rpm only the lower injector is working. Above 5500 rpm both injectors are activated. The system uses 40mm throttle bodies.
New Denso injectors with 12 laser-drilled holes deliver a finely atomized fuel mixture for optimum combustion efficiency and power.
Auto enriching system is integrated into PGM-FI module, eliminating the need for a manual choke.
Two-stage ram-air system provides a high volume of cool air to the airbox for linear power delivery and incredible engine performance.
Airbox volume increased to 15 liters (compared to CBR600F4i) for improved performance.
Cylinder head features angled valve inset to improve air flow.
Cylinder head features two springs per intake valve and two springs per exhaust valve for optimum high-rpm valve operation and durability.
Direct shim-under-bucket valve actuation ensures high-rpm performance and durability and offers 16,000-mile maintenance intervals.
New lighter pistons, piston pins and nutless connecting rods contribute to higher revving engine.
New double-pivot cam-chain tensioner improves cam chain durability.
Starter gears moved to the right side for increased lean angle.
New lightweight aluminum oil cooler.
Center-up muffler design increases lean angle and reduces wind drag.
Smooth-shifting close-ratio six-speed transmission is closely matched to the engine's powerband.
Chassis/Suspension

Completely new die cast aluminum frame utilizes new manufacturing methods to provide optimum rigidity while reducing weight. Frame is tuned for precise handling characteristics.
Large, 45mm cartridge front fork offers rebound and compression damping and spring preload adjustability.
New Unit Pro-Link rear suspension system is patterned after RC211V GP racer. In this system, the upper shock mount is contained within the swingarm rather than the frame. With no top frame-mount for the shock, this unique system eliminates negative suspension energy from being transmitted into the frame, allowing optimum frame rigidity and improved rideability out of corners. The HMAS shock offers rebound and compression damping, and spring preload adjustability.
Rear swingarm technology derived from RC211V.
Braking system features twin four-piston front calipers, dual 310mm front discs and a single 220mm rear disc for optimum stopping power.
New center-up exhaust system features four-into-two-into-one design for increased performance and aerodynamics.
Handlebars located below top triple-clamp for precise handling.
Additional Features

Industry-leading ergonomic design features maximum rider comfort for minimum fatigue in all riding conditions.
Centrally mounted 4.8-gallon fuel tank is positioned low in the frame, increasing mass centralization and allowing a more compact design. This design positions the rider 70mm forward for optimum handling.
New plastic tank shell cover protects tank and airbox.
New Line Beam Headlight features three- piece reflector design (first in the world) utilizing two H7 bulbs for optimum light distribution, and unique compact design.
New instrumentation is more compact and features tachometer, speedometer and fuel gauge.
Attractive hollow-spoke aluminum alloy wheels feature race spec 3.5 x 17-inch front and 5.5 x 17-inch rear dimensions.
Increased radiator capacity to match increased engine performance.
New one-piece fan assembly increases cooling efficiency.
Maintenance-free battery.
Optional seat cowl.
Compact rear cowl storage compartment for U-type locking devices (lock not included) under the passenger seat.
Folding aerodynamic mirrors.
Integrated ignition switch/fork lock for added security.
Convenient push-to-cancel turn signal switch.
Transferable one-year, unlimited mileage limited warranty; extended coverage available with a Honda Protection Plan.
Ownership includes one-year complimentary Membership in the Honda Rider's Club of America(tm). Benefits include discounts, travel benefits, roadside assistance and much more. For HRCA(r) details, call 1-800-847-HRCA.
Specifications

Model: CBR600RR
Engine Type: 599cc liquid-cooled inline four-cylinder
Bore and Stroke: 67mm x 42.5mm
Compression Ratio: 12.0:1
Valve Train: DOHC; four valves per cylinder
Carburetion: Dual Stage Fuel Injection (DSFI)
Ignition: Computer-controlled digital transistorized with three-dimensional mapping
Transmission: Close-ratio six-speed
Final Drive: #525 O-ring-sealed chain
Suspension

Front: 45mm HMAS cartridge fork with spring preload, rebound and compression damping adjustability; 4.7 inches travel
Rear: Unit Pro-Link HMAS single shock with spring preload, rebound and compression damping adjustability; 4.7 inches travel
Brakes

Front: Dual 310mm discs with four-piston calipers
Rear: Single 220mm disc
Tires

Front: 120/70ZR-17 radial
Rear: 180/55ZR-17 radial

Wheelbase: 54.7 inches
Rake (Caster Angle): 24.0°
Trail: 95mm (3.7 inches)
Seat Height: 32.3 inches
Dry Weight: 370 pounds
Fuel Capacity: 4.8 gallons, including 0.9-gallon reserve
Colors : Red/Black, Black, Pearl Yellow
California version Meets CARB 2004 emissions standards.