Cycle News is a weekly magazine that covers all aspects of motorcycling including Supercross, Motocross and MotoGP as well as new motorcycles
Issue link: https://magazine.cyclenews.com/i/128378
2006 BMW R 1200 RT & R 1200 ST Anot.her New Boxer The motor in the new RT/ST is a refinement of the motor that made its debut in the GS last year. Some of the changes have been made due to the application, but some are simply progressions. BMW claims that the motor's power output has been increased by 10 horsepower. without sacrificing any of its torque (85 ft.-Ibs.). Changes to the cylinderhead design are responsible for the increase. The compression ratio was raised from I I: I to 12: I, which now requires the use of premium fuel. The four-valve-per-cylinder heads feature new camshafts (one per cylinder). which actuate the valves via rocker arms. The valves themselves are filled with sodium to help dissipate heat more efficiently. Additionally. the heads feature two spark plugs per cylinder to help burn the fuel/air mixture more efficiently. The cylinder bores remain the same 101 mm. but the stroke is now 2.5mm longer. This oversquare architecture has allowed the redline to be raised by 500 rpm to 7500 rpm. The slower traffic, splitting lanes or maneuvering around parking lots. The ST's biggest drawback is that it doesn't really turn as quickly as a sport-touring motorcycle should. Despite the fact that the bike weighs less than the RT, it requires more effort at the bars than it should. To be honest, the ST seems lost somewhere between the R I I SO R and the RT, matching neither of those two bikes' attributes. If you are looking for a lighter RT and want to save almost $4K. this is the bike for you. If you are looking for a Boxerpowered sport-touring bike. an R I 100 S with bags, an R I I SO R or a GS is the way to go in my opinion - or just buy an RT. and enjoy all of the creature comforts. BMW did a much better job of executing what it set out to accomplish on the RT than on the ST I think the RT is a massive improvement over an already good performing and popular bike. The RT does it all and makes everything seem a lot easier than it should. The weight-loss program. added features. new styling and improved motor make the RT a clear winner over it's own sibling, and yes it's worth every extra penny. The RT is available in three colors: Piedmont Red Metallic, Granite Gray Metallic and Dark Graphite Metallic. The ST is available in six different two-tone color combos: Granite Gray/Light Magnesium. Piedmont Red/Light Magnesium. Sydney Blue/Ught Magnesium. Granite Gray/Dark Graphite, Piedmont Red/Dark Graphite and eN Sydney Blue/Dark Graphite. new lighter pistons travel in aluminum cylinders that have been treated for wear resistance and eliminates the need for liners. One of the keys to the new-generation 80xer engine is the addition of a balance shaft. The 80xer design has perfect primary balance, but that doesn't mean that it eliminates all unwanted vibration. So, a counter balancer was added which not only eliminates the secondary vibrations but also allows the engine speed to be increased without overstressing engine components. Like the GS before it, the RT/ST engine uses BMW's 8MS-K engine management system. The new computer controls the fuel-injection and ignition systems, in addition to other systems. Information is fed to the computer via sensors throughout the bike, including dual throttle-position sensors and twin oxygen sensors. It also features an antiknock sensor, which can compensate if premium fuel is not available. The computer also has the ability to fire the two spark plugs per cylinder separately if needed for more efficient fuei/air burn. (They could only fire simultaneously on the old motor.) The motor still employs a three-way catalytic converter within a stainless-steel exhaust system for improved efficiency and lower emissions. The GS/RT/ST all share the tranny that debuted in the GS last year. It still incorporates a large dry clutch. which helps keep the engine and transmission oil from becoming contaminated. The six-speed gearbox no longer features the "wide-ratio" gap between fifth and sixth gears, which improves responsiveness dramatically up top. New bearings and new materials on the three-shaft gear cluster have extended service life to 25,000 miles. The internal transmission ratios are exactly the same as on the GS, but the final drive ratio is a taller 2.62: I (2.82: I on the GS). SPECIFICATIONS BMW R 1200 RT LIST PRICE The RT's side cases fit snug and tight against the bike for improved aerodynamics. (Left) This image shows the range of the adjustable windscreen. 44 W\AY 18, 2005 • CYCLE NEWS $ I7,490 ($18,240 with optional ESA) DISPLACEMENT 1170cc ENGINE TYPE Air/oil-cooled. horizontally opposed twin BORE x STROKE 101 x 73mm COMPRESSION RATIO 12: I CARBURETION .. Electronic fuel injection IGNITION 8MS K TRANSMISSION Six-speed STARTING SYSTEM Electric FUEL CAPACITY 7.1 gal. WHEELBASE 58.4 in. RAKE/TRAIL. 26.6'/109.22mm SEAT HEIGHT 31.9-32.7 in. FRONT TIRE 120/70ZR 17 REARTIRE I80/55ZRI7 FRONT·WHEEL TRAVEL .4.7 in. REAR·WHEEL TRAVEL 5.3 in. FRONT BRAKE Dual 320mm discs w/ABS REAR BRAKE 5ingle 264mm disc FINAL DRIVE Shaft CLAIMED DRY WEIGHT 505 Ibs. CLAIMED WET WEIGHT 571 Ibs. w/o cases BMW R 1200 ST LIST PRICE $ I 4.990 DISPLACEMENT 1170cc ENGINE TYPE Air/oil-cooled. horizontally opposed twin BORE x STROKE 101 x 73mm COMPRESSION RATIO 12:1 CARBURETION .. Electronic fuel injection IGNITION BMS K TRANSMISSION .six-speed STARTING SYSTEM Eleetric FUEL CAPACITY 5.5 gal. WHEELBASE 59.1 in. RAKE/TRAIL 27'/1 I 1.76mm SEAT HEIGHT 3 I. 9-32.7 in. FRONT TIRE 120/70ZR 17 REAR TIRE 180/55ZRI7 FRONT·WHEEL TRAVEL .4.3 in. REAR·WHEEL TRAVEL 5.5 in. FRONT BRAKE Dual 320mm discs w/ABS REAR BRAKE Single 264mm disc FINAL DRIVE .shaft CLAIMED DRY WEIGHT 452 Ibs. CLAIMED WET WEIGHT 505 Ibs.