The Monster S4Rs is a bike without compromise, a true superbike in every way. Only the full fairing has been removed. Nothing else has been sacrificed.
All the legendary Superbike power and character of the potent desmodromic Testastretta engine remains. The new, amazingly powerful Ducati Monster S4Rs is as unique as its name, and the pace-setter that all other naked models must measure up to. Ducati leads the way in unfaired motorcycles; always coming up with something new and original and determined to maintain it.
The Monster S4Rs is a masterpiece of technology and design. One glance at the bike, even parked, is enough to make your heart miss a beat and your breathing quicken. Just look at the harmony of the design and the precision of the engineering.
In its premier performance, and taking centre stage is the Testastretta engine, embraced by Ducati’s legendary trellis frame and the unmistakable styling that has always characterized a Monster.
The styling is that of a spectacular, custom, the sort of bike we could previously only dream of. Yet the Monster S4Rs Testastretta is impressively real. The sensation of power oozes from every pore. In addition to the common features shared by all Ducati Monsters with single sided swingarms, like the small upper fairing, vertically stacked twin exhausts and longitudinal stripe (bigger and centrally positioned on the S4Rs), the S4Rs also incorporates a large number of eye-catching racing components.
The S4Rs features new graphics and colour schemes to enhance the 999-derived front end and the Y-spoke wheels that recall the racing origins of this unfaired superbike. In fact, Ducati Corse has contributed a large number of small but important details to this Monster, details that might not be noticed under a full fairing but that cry out for attention on this meanest of all Monsters, like the triangular oil cooler for example.
Add to that a long list of carbon fiber parts, plus the stunning twin aluminum exhausts and the performance first priority of the S4Rs is obvious. The Monster S4Rs looks aggressive and stunningly essential. It tells you in no uncertain terms what sort of performance, technology, design and passion lies in front of you. In short, the S4Rs Testastretta is a dream machine, with a look and feel that satisfies even before you twist the throttle.
Technical Features Frame and Chassis: The central feature of this most powerful Monster’s chassis remains its trellis frame formed in high strength ALS 450 steel tubing. The frame of the new Monster S4Rs boasts 5% greater torsional rigidity than that of the previous Monster S4R, due to design improvements around the airbox.
The swingarm is Ducati’s exclusive single sided unit that equips all members of the SR family. This elegantly crafted rear suspension component is made from a complex tubular aluminum trellis.
The swingarm on the top of the range S4Rs is finished in black in keeping with Ducati Racing style.
The tapered aluminum alloy handlebars feature a variable cross-section. Diameter is 22 mm at the grips, but increases to 28 mm at the centre to give the best possible weight to rigidity ratio. This design allows a reduction in the thickness of the handlebar tube from the usual 5 mm to 4 mm.
As with all SR series Monsters, compared to most naked motorcycles, the seat-handlebar-footpeg position is unique and decidedly aggressive and sport oriented.
The chassis of the Monster S4Rs boasts a 1440 mm wheelbase and a trail of 96 mm, achieved by offsetting the fork legs 30 mm ahead of the steering axis and giving the steering head a rake angle of 24°.
As you would expect of a true unfaired Superbike, the new Monster S4Rs is equipped with some of our best components, derived directly from the world of racing.
The front end features 43 mm Öhlins upside down forks with titanium nitride coated stanchions for smoother action and more sensitive control. This fork is almost identical to those used on Ducati’s top of the range superbikes, and boasts adjustable compression and rebound damping, and spring preload.
The rear shock is also Öhlins , and incorporates a piggy-back reservoir, and also permits a wide range of adjustments for compression, rebound and spring preload. One important detail is the innovative preload adjuster ring, made from a plastic and carbon fiber mix for easier adjustment and reduced weight. This new shock weighs in at only 2,690 grams (18% or 580 grams lighter than the unit on the S4R).
Just like the top models in the Ducat supersport range, the S4Rs offers the unique Ducati rear height adjustment system, allowing the rider to set rear ride height separate from, and without effecting spring pre-load.
With a professional suspension configuration such as this, every rider can set up the bike to match riding style and surface conditions, whether it be on the road or track.
The attention to detail that Ducati has put into the design of the new S4Rs is further conformed by the choice of wheels, carefully selected for unbeatable rigidity and lightness.
At the rear we find a new, super-lightweight Marchesini aluminium wheel with 5 “Y” spokes, 1,300 grams (23%) lighter and with 18% less inertia than the rear wheel fitted to the S4R. The result is dramatically reduced unsuspended mass for easier, more precise control.
The front wheel is also by Marchesini, again with 5 ‘Y’ spokes, in aluminium alloy. This is the same wheel that is fitted to the Ducati 999S.
Of the many racing components that enhance the looks and technical excellence of this mighty Monster, the Brembo braking system is one of the first to catch the eye. At the front the S4Rs is equipped with a radial master cylinder with a 19 mm piston and separate reservoir, coupled with a pair of radial calipers, with four 34 mm pistons and four separate pads.
The Brembo logo is milled into the caliper casting and finished in red paint, just as on the Desmosedici GP6. The two discs are 320 mm in diameter, 4.5 mm thick and are mounted on special aluminium alloy flanges.
The rear braking system is also by Brembo and comprises a master cylinder with an 11 mm piston and a fixed caliper with two opposed 32 mm pistons and a 245 mm disc.
Exhaust System The S4Rs is equipped with the latest evolution of the exhaust that equips the entire SR range. This layout incorporates a special pre-silencer slung under the engine and connected to two compact vertically stacked silencers mounted high to one side.
The exhaust system has been completely redesigned to squeeze the last ounce of power out of the low sump Testastretta. The primary down pipes and secondary collectors have increased to 45 mm in diameter (vs. 40 mm of the S4R), and the exhaust gas path has also been redesigned and updated to bring emissions within the strict limits imposed by Euro 3 legislation.
The Lambda probe inside the pre-silencer maximizes the efficiency of the new three-way catalytic converter, also housed inside the pre-silencer.
The S4Rs’s new exhaust system is made even more eye-catching by three carbon fibre heat guards fitted to the top silencer and to the secondary collector pipes to protect the rider’s feet.
The electrical system of the new Monster S4Rs has been totally revolutionized to eliminate all visible cables, to achieve a clean uncluttered look, and to provide easy access to all mains parts. The key components, such as the electronic control unit, battery, fuses and relays are located above the vertical cylinder head and are easily accessible simply by lifting the tank.
Magneti Marelli ’s 5AM electronic control unit has been selected to manage the Testastretta’s fuel injection and ignition systems. This unit incorporates hybrid electronic circuits on multistrate ceramic surfaces with an exceptionally high level of integration. The unit is extremely compact in size as a result.
The 5AM has a flash EPROM to allow operating parameters to be reprogrammed repeatedly during development and tuning. The unit also houses the power circuits for the two ignition coils and for the two IWP 189 12-hole injectors (one per cylinder) as used on our race bikes which provide superior atomization of the fuel spray.
The use of a stepper motor to provide automatic control of idling speed is another major innovation. This method of idling control is extremely effective in maintaining smooth and regular idling even as the engine’s component characteristics change over time as the result of normal wear and tear on mechanical engine parts. The throttle body no longer needs a cold starting device, and this in turn means a far simpler butterfly valve control system. The idling speed regulator has a horizontal slider, moved by a lead nut system connected to a stepper motor.
The S4Rs clearly surpasses all expectations when it comes to the engine. It is the new reference point for all large bore unfaired bikes, created by the overwhelming desire and delicate operation of transplanting a Testastretta twin into the trellis frame of the Monster.
The compact 90 º twin cylinder design that graces all Ducatis enables us to make uniquely narrow and agile motorcycles that are surprisingly similar to racing machines. This twin cylinder power plant delivers amazingly muscular power compared to the average four cylinder engine, to say nothing of fantastic torque that delivers thrilling acceleration and unrivalled riding sensations.
The Testastretta engine’s capabilities needs little introduction. Its prestige and fame have been won on the circuits of the World SBK Championship. This twin is the maximum technical expression of the ingenuity of Ducati, and outclasses even the most powerful four cylinder engines. Its sound alone is enough to get the adrenaline pumping!
The Testastretta represents a milestone in Ducati’s Superbike history. It owes its name to the special configuration of the cylinder head, which minimizes the angle between the valves. Its “narrow head” design creates a compact, cleaner and therefore more efficient combustion chamber. The flat crown pistons are the optimum shape to produce a smooth and linear flame front.
The special head design, combined with advanced electronic engine management, also ensures efficient combustion at all engine speeds, for smooth, controllable power. The S4Rs uses the most advanced “low sump” version of the Testastretta engine. This is the technical solution used on racing Ducatis, with the sole difference being that the sump on the production engine is die cast versus the sand cast of the race bikes. The special shape of this sump ensures that the oil pump remains immersed in lubricant under the most extreme lean angles and G-forces, on road and track alike.
A large number of engines parts of the Testastretta engine have been specially designed and re-engineered to enable it to best suit the dynamics and style of the flagship of the Monster range. Those that stand out the most are the reshaped sump, modified at the rear to accommodate the single sided swingarm, the new carbon fiber timing belt covers, and the new cam covers, which are smaller in size and secured by just four screws.
The throttle bodies have also been totally redesigned. On the mechanical side, the 50 mm throttle bodies, brackets, linkages and pulley are all new. In the electrical and electronic systems, the advanced 12-hole IWP 189 injectors, the potentiometer and the stepper motor for automatic idling speed control are also new.
The engine delivers an amazing 130 HP at 9500 rpm, with torque peaking at 10.6 kgm at 7500 rpm. The smooth and progressive power delivery from this engine makes the Monster S4Rs a real pleasure to ride. The Testastretta’s vital statistics include a stroke of 63.5 mm and a bore of 100 mm. The inlet valves are 40 mm in diameter and the exhaust valves 33 mm. Valve lift is 11.71 mm for the inlet valves and 10.13 mm for the exhaust valves.
Style and Finish The Ducati Monster S4Rs is not just another sports bike, nor a mere superbike without a fairing. It could be called “super-bike”, packed with parts and solutions taken directly from the world of motorcycle racing.
The trellis frame, central to the appeal of the Monster family, has been made even more beautiful by eliminating all the small wire ties and more thoughtful routing of the electrical cables.
The large number of components formed in carbon fiber demonstrates how much attention Ducati has paid to getting even the smallest details right. The front mudguard has been redesigned specially for the S4Rs, as have the radiator guards, timing belt covers, side panels and exhaust system heat shields for the secondary collector pipes and top silencer.
The looks of the S4Rs are enhanced by original new graphics. A brand new logo has been conceived to emphasize the exclusiveness of the bike. You can find it on the top of the tank, on the new instrument panel graphics and on the aluminum inserts of the side panels. The fuel tank, fairing and seat cover graphics are new too.
The longitudinal stripe that has always characterized the SR range of the Monster family is far broader and has moved to the bike’s centerline, where it runs down the nose fairing, tank and seat cover. A great deal of care has been taken in selecting the bold new colour schemes for the new S4Rs. You can choose from three alternative finishes: original new pearl white with red stripe, with red frame and white wheels; quintessential Ducati red with white stripe, with red frame and black wheels; and aggressive gloss black with light grey stripe, with black frame and black wheels. The unique swingarm is finished in black on all three versions.
Even the brakes contribute to the S4Rs’ stunning looks: the brake calipers have the Brembo logo milled into them, and then the logo is finished in red paint to create a front end worthy of a true racer.
The care and attention dedicated to the finish of this super-naked even extends to parts that are often considered of secondary importance. Take the cooling system for example. The radiator has a new shape to accommodate new, more elegant bullet shaped fans, and is protected at the sides by two carbon fiber guards. The pipe that runs from the radiator to the coolant pump is in aluminium rather than rubber. And the oil cooler fixed to the horizontal cylinder head has a new trapezoid shape.
There is even one new technical solution that might easily go unnoticed. Though identical in appearance to those of all other SR Monsters, the fuel tank is completely new and boasts a bottom profile that has been thoroughly redesigned to house a brand new, ultra-compact fuel pump.