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Archive for the ‘2006’ Category

With the BMW R1200R famed reliability meets the tuning fingers of a joker. There’s a fair wallop of bottom end grunt and top end kick – more than any naked bike has a right to have. Even though the old flat-twin is very old design-wise, modern internals, electronics and injected fuelling ensure the Boxer motor lives on for a while longer to keep BMW purists happy. Shaft drive is a god-send for the less mechanically minded.

With an engine design that can be traced back to before most of us were born, and a rolling chassis that has tried and trusted components, the reliability of the BMW R1200R is never going to be an issue. However, modern electronics suffer on all bikes because of vibrations and hostile weather, so no one can guarantee a bike to be free from problems. If it helps, BMW has one of the strongest ‘faithful’ group of riders because it seems its motorcycles just keep going and BMW aftercare is a committed one.

Telever front suspension (relies on a single main spring under the steering head) is unique to BMW, as is the Paralever shaft arm. Used on its touring models the whole system is a testament to stability and a role model for coping with UK roads. Now lighten the steel-based frame, add sports-like steering and you get a bike, the BMW R1200R, that rolls over quicker than a nervous spaniel. Traffic dodging and A-road blasts are simple and fun, which sums the motorcycle up completely.

If the Japanese manufacturers produced an £8300 bum-basic naked with the R1200R’s performance then sales-wise it’d fall flat on its arse. So how comes BMW can get away with it? Simple really, because it is a BMW and with BMW motorcycles comes high resale values. Value for money? Not if you’re into bikes like Kawasaki’s Z1000, or Bandit Suzukis, but then they don’t have shaft drive and will never command a good resale value.

With the exception of a three-way height adjustable seat as standard, the R1200R is bum-basic for a BMW, and that’s why the price is kept low (for a BMW). But as it is a BMW the list of optional riding equipment is long (and pricey): Electronic Suspension Adjustment (ESA), ABS, tyre pressure monitoring, soon-to-come traction control etc.

One of the central concepts that drove development of the CBR600RR is mass centralization; that is, concentrating the component masses as close to the motorcycle’s center as possible. When a rider initiates a turn, the motorcycle rotates around its roll axis—an imaginary fore-and-aft horizontal line drawn through the center of mass of bike and rider—as it leans into the turn. Placing the major masses (engine, fuel, rider) closer to this roll axis results in a motorcycle that reacts more quickly and smoothly to control inputs at the handlebars. The concept of mass centralization has been a guiding principal at Honda for decades, but the application to the RR takes the concept to a whole new level.

Honda engineers looked at the CBR600RR as an organic whole for centralizing mass. Every change, every hard part was related and affected others. Part of the approach calls for lightening as many pieces as possible that are far from the center of mass. That gave rise to the RR’s compact Line-Beam headlights, with their high-illumination three-piece reflectors-another Honda first for use on a production motorcycle; a lighter, more compact wheel hub design; slimline LED taillight; an analog/digital fully electronic instrument panel that’s one of the lightest and slimmest ever mounted on a street bike; plus a host of other changes.

The RR excels in the nip-n-tuck of urban survival. It’s tall, light and nimble and has an amazingly broad torque curve and excellent pick up from the traffic lights and multitudes of stop signs that seek to ‘calm’ traffic but are a total nuisance. With a limited fairing the RR is less comfortable on the open highway. Below 100mph the bike is fine and the actual riding position is fairly comfortable, with not too much strain on the wrists.

Honda will know all about these minor failings, it’s obvious that the bike wasn’t designed to be a great tourer – they have plenty of those on the fleet and non have RR decals on the tail. Compared to the 2003 model, the new CBR 600RR received a major revision with new body work, fully adjustable inverted front forks, a set of track-inspired disc brakes with radial-mounted four-piston calipers, and an entirely new aluminum frame, swingarm and rear shock. These changes along with additional refinements to the engine and exhaust system all came together to bring CBR600RR’s weight down nine pounds.

Unique Features

- Unit Pro-Link® rear suspension and swingarm design inspired by RC211V.

- Dual Stage Fuel Injection (DSFI) system features two injectors per cylinder.

- High-revving engine redlines at 15,000 rpm.

- RC211V-style center-up exhaust system.

- Radial-mount front brake calipers

- 41mm inverted front fork.

- Centrally located fuel tank increases mass centralization and allows more compact frame design.

- Line Beam Headlights features three-piece reflector design.

- Bodywork resembles championship.

Engine

The CBR600RR is powered by a 599cc liquid-cooled inline four-cylinder. It does share the same bore and stroke dimensions (67mm x 42.5mm) as the F4i’s engine, but that was decided only after extensive testing with other cylinder dimensions. Honda’s engineers found the F4i’s displacement numbers would also be ideal for the RR’s performance goals.

The engine has been significantly improved over the F4i. Pistons, pins, and connecting rods are lighter than those of the F4i, increasing overrev capacity with a 15,000rpm redline. Larger intake valves improve flow, with a new dual-stage tensioner preventing whipping of the cam chain at higher rpms. The sump is now deeper to minimize oil splash, resulting in less internal friction.

The ram-air induction system supplies the motor with more air than that of the F4i, using a revised ducting system with larger ducts. Wind tunnel testing showed that larger outer ducts increase the required steering effort at higher speeds. Holes have been cut into the outer ducts on the 600RR to minimize that effect, a technique Honda has successfully implemented on GP bikes for years. They also look very cool and were a constant source of comments at the biker pit stops.

Engine/Drivetrain Features

- 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 (CBR®600F4i redlines at 14,200), wider powerband and more over-rev than CBR600F4i.

- Compact engine length (236mm) positions the rider forward for more precise handling.

- Iridium-tip spark plugs improve fuel combustion and performance.

- Dual Stage Fuel Injection 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.

- Denso injectors with 12 holes per injector 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.

- Cylinder head features angled valve inset to improve airflow.

- 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.

- Light pistons, piston pins and nutless connecting rods contribute to higher-revving engine.

- Double-pivot cam-chain tensioner for cam chain durability.

- Right-side starter gears for increased lean angle.

- Lightweight aluminum oil cooler.

- Smooth-shifting close-ratio six-speed transmission is closely matched to the engine’s powerband.

Chassis

Honda’s CBR600s have always had a reputation for exemplary handling, a reputation engineers wanted to enhance with the all-new CBR600RR. It was a daunting task, but what better place from which to draw inspiration than the MotoGP champion, Honda’s RC211V?

The CBR600RR’s frame, for example, makes use of the mass centralization ideas proven so well on the RC211V, starting with placing the fuel tank low in the aluminum frame. That facilitated positioning the engine and rider farther forward, pushing all three closer to the center of mass than with the F4i’s frame.

And the RR took yet another chapter from the RC211V’s winning play book, with its Unit Pro-Link rear suspension—technology never before seen on a street bike. Unit Pro-Link attaches the top of the shock absorber to the heavily braced aluminum swingarm, rather than to an upper-rear frame crossmember. As the rear wheel passes over a bump, the shock is compressed at the bottom by a set of links (see Unit Pro-Link technical feature for more details).

A host of benefits cascade from this simple, elegant idea. It facilitates placing the fuel tank low, because there’s no crossmember locating the top of the shock. Furthermore, with Unit Pro-Link, the shock absorber’s loads don’t get fed into the frame’s downtube structure, which allows the engineers unprecedented freedom in frame design, so they can tune the frame for very specific characteristics.

Chassis/Suspension

- Die cast aluminum frame utilizes new manufacturing methods to provide optimum rigidity while reducing weight. Frame is tuned for superior and precise handling characteristics.

- 41mm inverted Honda Multi-Action System (HMAS) cartridge front fork features spring preload, rebound and compression damping adjustability for precise action.

- Unit Pro-Link rear suspension system is patterned after RC211V GP racer. In this two piece shock design 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 reduces negative suspension energy from being transmitted into the frame, allowing optimum frame rigidity and improved rideability out of corners.

- Braking system features twin four-piston radial mounted front calipers, dual 310mm front discs and a single 220mm rear disc for optimum stopping power.

- Center-up exhaust system features four-into-two-into-one design for increased performance, aerodynamics, and lighter weight.

- Lightweight triple clamp.

- Handlebars located below top triple-clamp for precise handling.