CBR600RR

1. Introduction

The much-loved CBR600RR has an impressive and hard-won racing pedigree. It was piloted to FIM World Super Sports championship victory every year from 2003 to 2008, and again in 2010, 2012 and 2014. It won the Asia Road Racing championship from 2012 to 2016 and the All-Japan Road Race championship ST600 class from 2003 to 2011, and in 2013, 2014, 2016 and 2019. Its engine also provided the power for Moto2 between 2010 and 2018.

The 600RR departed from Honda’s European showrooms at the start of 2017 as the trend away from supersport machinery towards naked and adventure models accelerated. In the intervening years, the middleweight sports category has seen a revival, and the model was reintroduced for 21YM in Japan and Thailand.

Now the time is ripe for the purest of all road-legal sports bikes to make its return to Europe. Loaded with cutting-edge MotoGP-inspired electronics and aerodynamics, the new 24YM CBR600RR is a rare, beautiful thing – a free-revving four-cylinder motorcycling gem that exists in a class of one.

Born ready to carve an elegant line on the open road or closed circuit, there’s no other riding experience quite like it.

2. Model Overview

Honda’s supersports icon returns to Europe with its 599cc, inline four-cylinder engine producing 89kW @ 14,250rpm, and benefitting from an assist/slipper clutch and standard-fit quickshifter.

An electronics package drawn from the RC213V-S and the CBR1000RR-R Fireblade includes Throttle By Wire control, 9-level Honda Selectable Torque Control (HSTC), Wheelie Control and Rear Lift Control.

At the centre of the action and managing all of the systems, including Cornering ABS, is a 6-axis Inertial Measurement Unit (IMU) as found inside its sibling, the CBR1000RR-R Fireblade. There are 3 default riding modes, plus 2 User modes for adjustment of Engine Power, Engine Braking, HSTC and Wheelie Control.

The chassis comprises a twin-spar aluminium frame, aluminium swingarm, 41mm Showa Big Piston USD front forks and Unit Pro-Link Showa rear shock. Four-piston radial-mount front calipers provide the braking power, and a Honda Electronic Steering Damper (HESD) extra stability.

The full colour TFT screen includes Street, Circuit and Mechanic modes. A Shift Up indicator and lap timer are also featured. Honda’s Emergency Stop Signal (ESS) and Honda Ignition Security System (HISS) are included in the specification.

Like all bikes in Honda’s supersport family, the 24YM CBR600RR is available in two colour options: under-the-radar Matt Ballistic Black Metallic, and evocative Grand Prix Red HRC TriColour, the signature colourway of Honda Racing Corporation (HRC).

3. Key Features

3.1 Engine

• Inline four-cylinder engine produces 89kW with 63Nm torque
• Assist/slipper clutch

The CBR600RR’s 599cc, 16-valve inline four-cylinder engine produces 89kW @ 14,250rpm, with 63Nm torque @ 11,500rpm. To achieve the power output at this rpm ceiling the materials used for the camshafts, valve springs and crankshaft have been upgraded for its return to manage both high-rpm inertia force and durability. Bore and stroke is set at 67mm x 42.5mm, with compression ratio of 12.2:1.

Every aspect of intake, combustion and exhaust has been through development since the CBR600RR was last on sale in Europe. To flow enough volume at high rpm throttle body diameter is 44mm. The port of the throttle butterfly valve and the intake-side valve have been shaped to allow the cross-section of the entire port (including the inside of the throttle body) to run smoothly, reducing intake pressure drop.

The combination of this smooth intake passage and Throttle By Wire (TBW) delivers smooth throttle control, especially at partial openings from fully closed. The inlet ports have been re-shaped, increasing flow capacity by 2.2%.

Valve timing has also been adjusted: closing of the inlet valves has been pulled back 5° with the exhaust valves opening 5° later, improving the intake efficiency of the fuel/air mixture and exhaust of combustion gas. Inlet valve diameter is 27.5mm matched to 22.5mm exhaust. For maximum cooling efficiency around the cylinder head, long reach spark plugs allow the water jacket to sit close to the plug hole and exhaust valve seat.

The 4-2-1 exhaust uses large bore diameters to enhance high-rpm gas flow; wall thickness has been carefully managed to minimise weight gain. The catalyser is also physically larger, and an important part of the EURO5 homologation process.

An assist/slipper clutch manages rear wheel ‘hop’ through rapid down changes and hard braking. It also reduces the physical force needed to operate it by 32% over a standard design and employs die-cast aluminium cams at both transmitting and receiving ends, with clearance between both optimised to improve lever feel.

3.2 Engine Electronics

• RC213V-S-derived Throttle By Wire (TBW) control system
• 9-level Honda Selectable Torque Control (HSTC)
• 3 default riding modes plus options to customise Power, Engine Brake, HSTC and Wheelie Control
• Quickshifter standard fitment

The Throttle By Wire (TBW) used by the CBR600RR is drawn from the CBR1000RR-R Fireblade and was developed on the RC213V-S. An Acceleration Position Sensor (APS), which interfaces with the throttle grip is built into the switchgear. It sends a signal to the ECU, which then sends a signal to the TBW motor that controls the butterfly. Crucially, the return spring and friction generated by the APS offers a completely natural throttle feel and control. It also offers the same controllability and feel across all of the power levels.

The electronic package that goes with TBW is also drawn from the Fireblade. 9-level (plus off) Honda Selectable Torque Control (HSTC) uses slip rate control (which monitors the rate at which slip is changing based on the ratio of front/rear wheel speeds) to smoothly moderate rapid wheel spin. It gives smooth, intuitive grip management, with software developed from wide-ranging, top-level feedback from around the world, including HRC’s riders. Level 1 has the weakest intervention, level 9 the strongest.

There are three default riding modes: Mode 1 (Fast Riding), Mode 2 (Fun Riding) and Mode 3 (Comfortable Riding) with 2 User options for a full custom setup across all of the parameters. Modes can be switched while riding (from the left handlebar switchgear), as can the HSTC level when in User 1 or 2.

Power (P) operates through levels 1-5 with 1 giving ultimate outright power. Engine Brake (EB) manages performance on a closed throttle through levels 1-3, with 1 being the strongest engine braking; Wheelie (W) manages through levels 1-3 (plus off) with 1 giving the weakest intervention.

Wheelie Control uses information gathered by the IMU on the CBR600RR’s pitch angle, along with front and rear wheel speed sensors to maintain torque and deal with the wheelie without sacrificing forward drive.

A standard-fit quick shifter delivers razor-fast changes, with short fuel cut time while shifting, and smoother torque pickup after shifting. It offers 3-level adjustment for feel.

3.3 Chassis

• Twin-spar aluminium frame, aluminium swingarm
• 41mm Showa Big Piston USD forks 
• Bosch 6-axis Inertial Measurement Unit (IMU)
• Honda Electronic Steering Damper (HESD)
• Four-piston, radial-mount front brake calipers and floating discs

For this latest incarnation of the CBR600RR Honda’s development engineers picked through the bike, front to back, looking for weight savings with performance enhancement to complement the addition of a Bosch 6-axis Inertial Measurement Unit (rather than 5-axis of the 21YM model) to the electronic package.

The updated IMU is key to the bike’s ability to build speed and measures every dynamic aspect, in each plane, calculating 100 times a second using Honda’s own algorithm and in turn managing the HSTC and Cornering ABS, which is a new technology applied to the 24YM CBR600RR.

It’s 2.5kg lighter than the ‘Combined-ABS’ electronic system of the previous design and employs a Nissin ABS modulator and ECU – which takes input from the IMU and deceleration and slip rate from the front/rear wheel speed sensors to manage brake pressure in a straight line and while cornering.

Rear Lift Control is also a new feature, and again uses IMU input to maximise braking performance while minimising rear wheel lift.

At the heart of the chassis is a hollow, die-cast twin-spar aluminium frame. Wheelbase is set at 1370mm, with rake of 24 ^o 06’ and 100mm trail. Length from swingarm pivot to rear wheel spindle is 569mm; the aluminium swingarm is also 150g lighter than the previous model, with each part redesigned to save weight but also to give the desired rigidity balance. Kerb weight is set at 193kg.

Fully adjustable Showa 41mm Big Piston USD forks offer high-quality suspension reaction and control. They’re also 15mm longer in the legs to allow flexible geometry changes. The fully adjustable Showa rear shock operates through Unit Pro-Link.

Up front, dual radial-mount four-piston calipers clamp 310mm floating discs; a radial-piston master cylinder is also standard fit. A rear, single-piston caliper works a 220mm disc. Cast aluminium wheels wear 120/70ZR17M/C  front and 180/55ZR17M/C rear tyres.

A Honda Electronic Steering Damper (HESD) – designed exclusively for the CBR600RR – operates relative to velocity and is ECU-controlled; at lower speeds its main valve opens, reducing damping force. At high speed the valve closes, increasing damping force for maximum stability.

3.4 Styling & Equipment

• Best in class aerodynamic performance
• Winglets generate downforce to enhance front tyre grip
• Full colour TFT screen

While it’s a stunning looking motorcycle, the CBR600RR’s styling also provides two performance upgrades: as a fully equipped road bike, the lowest Coefficient of Drag in class, at 0.555 (with rider in a racing tuck), and winglets to improve corner entry stability and turning ability while accelerating.

A guiding phrase used by Honda’s development team for the bodywork was ‘Embody the functional design in pursuit of high-speed on-track performance.’ Everything learnt producing the CBR1000RR-R Fireblade, and before it the MotoGP-derived RC213V-S, was applied with a focus on the mass centralisation of form.

As a result, the sharp, super-compact LED headlights, indicators and ABS modulator are lighter compared to the previous design. The riding position too has been made deliberately flexible for road and track; the fuel tank cover sits 10mm lower, allowing the rider to tuck in neatly at high speed. It’s also slimmer and designed to allow the rider’s arms to also have a natural place at speed. The screen sits at a 38°, to maximise aerodynamic efficiency relative to any position the rider might use on track. Seat height is set at 820mm.

Radiator cooling efficiency is focus of the mid-section of the fairing, and airflow speed and pressure into the front wheel housing has been optimised for both flow in and out. The lower fairing extends close to the rear wheel and is shaped to move airflow downwards. This reduces the amount of direct air pressure exposure against the tyre, reducing overall resistance.

The winglets generate downforce – maintaining front tyre load – on corner entry as the rider leans in and releases the front brake. And overall cornering stability is improved, as is corner speed. Carefully designed, the winglets do not interfere with the bike’s handling agility, with the vertical shaping suppressing the development of vortices.

A full colour TFT screen includes Street, Circuit and Mechanic modes. A Shift-Up indicator uses 5 white horizontal LEDs above the central display and turn on and flash at the pre-set rpm for shifting. Information available also includes lap time, number of laps and fastest lap.

Lighting is LED. The dual front headlights are lightweight in design and allow the optimal intake area for the central ram-air duct. Honda’s Emergency Stop Signal (ESS) is linked to the ABS modulator and activates the front and rear indicators under sudden, hard braking to warn other road users.

Honda Ignition Security System (HISS) uses interlock control between the ID tag in the key and internal ID of the engine ECU so there’s no way to start the engine without the key. A red LED on the dash flashes every 2.5 seconds for 24 hours once the ignition is off and even when it stops flashing, HISS is still on.

A small final detail to note - the CBR600RR wears its racing DNA in the shape of Honda’s signature wing on its fuel tank cover – exactly the same as the RC213V-S.

4. Accessories

Two Genuine Honda Accessories Packs are ready to go for the CBR600RR:

Racing Pack

This pack underlines the racing pedigree and sportiness of the CBR600RR. The Oil Filler Cap includes an HRC logo, the Carbon Look Tank Pad wears a CBR logo and Wheel Stripes are finished in HRC Tri-Colour and Honda Racing Logo. A Seat Cowl replaces the pillion seat and is available in Black or Red.

Comfort Pack

Take the supersports experience further... Functional rear seat bag that is specifically adapted to the tapered shape of the rear seat. Featuring a capacity of 15L that can be expanded up to 22L and always stable during riding thanks to its specific attachment system. 5-level Heated Grips extend the riding year, while a USB-C charging socket adds convenience.

HRC Race Kit

HRC has developed a Race Kit for the CBR600RR that ups engine performance, heightens cornering ability and grip, and saves weight. Available to buy as a complete kit – and for circuit use only – all road safety items are neatly removed and HRC kit parts, including ECU, wiring harness, cylinder head gasket, big radiator, racing exhaust, front/rear suspension and brake discs plug straight in.