HARLEY-DAVIDSON SPORTSTER S – DRIVE AND TECHNOLOGY
Revolution Max 1250T engine, riding modes, infotainment display and cornering assistance system package from Harley-Davidson
NEW ISENBURG (July 13, 2021) - With the Sportster S, Harley-Davidson presents a brand new and powerful factory custom bike and at the same time ushers in the latest chapter in the Sportster history - with a dynamic experience on the country road and state-of-the-art technology a successful synthesis of safety and driving pleasure.
Revolution Max 1250T
The new Sportster S is powered by the Revolution Max 1250T engine, a liquid-cooled V2 that is completely tuned for power from the basement. The torque curve remains flat across the entire speed range - a beefy power delivery for dynamic acceleration from a standstill and powerful pulling power in the middle speed range.
- Displacement: 1,252 cm³
- Bore x Stroke: 105.0mm x 72.3mm
- Power: 90 kW (122 HP)/7,500 rpm
- Maximum torque: 125 Nm/6,000 rpm
- Rotation speed: 9,500 rpm
- Compression ratio: 12.0:1
The Revolution Max 1250T is derived from the Revolution Max 1250 engine of the Harley-Davidson Pan America 1250 models, from which it differs primarily in the following features:
- Cylinder heads with smaller valves, narrower channels and a modified combustion chamber ensure increased flow speed and thus rapid gas exchange and optimal filling of the cylinder, which increases torque in the low and medium speed range between 3,000 and 6,000 rpm.
- The new combustion chamber geometry also requires an adapted shape of the pistons.
- Intake funnels that have been redesigned in terms of length and shape as well as the optimized volume of the airbox ensure the best possible performance across the entire usable speed range.
- Optimized cam profiles and timing of the variable valve control also make a decisive contribution to the desired performance characteristics.
Revolution Max 1250T – Highlights
- V2 architecture: A longitudinally installed V2 engine with a 60-degree cylinder angle is characterized by a narrow design that allows the masses to be grouped close to the center of gravity for active handling without affecting the space available for legs and feet. Two throttle bodies in a flow-efficient downdraft arrangement between the cylinders minimize turbulence and flow resistance in the intake tract.
- Weight-optimized design: With its low weight, the engine also helps to keep the overall vehicle weight low. This benefits acceleration, agility and braking behavior as well as consumption.
- The finite element method and modern optimization processes in engine development help to reduce the mass of cast and molded components.
- The weight-saving design features also include one-piece light metal cylinders with galvanic nickel-silicon carbide coating.
- The valve and primary drive covers are made of lightweight magnesium alloy.
- Drive as a supporting chassis component: The Revolution Max 1250T is also integrated as a supporting part in the chassis of the new Sportster S.
- The engine fulfills two functions: It serves as a drive and is also a structural element of the chassis.
- By dispensing with a classic main frame, the chassis has a particularly low weight and extremely high torsional rigidity.
- A front frame element, a middle segment and the rear frame are bolted directly to the engine.
- The engine is designed to be particularly robust and rigid so that it can effectively fulfill its function as a chassis component.
- The advantage for the driver is optimized driving characteristics thanks to significant weight savings, high torsional rigidity and masses centralized directly at the center of gravity.
- Liquid cooling: Liquid cooling ensures a stable, controllable engine temperature for consistent performance under a wide range of environmental conditions and in all driving situations - whether in cold or warm weather, at high speed or in traffic jams, in relaxed or sporty driving. The engine oil temperature is also regulated via a cooling system, which ensures optimal lubrication and long oil change intervals even under the toughest operating conditions.
- Four-valve cylinder heads: Cylinder heads with four valves each allow particularly large valve cross-sections. Harley-Davidson has optimized the gas flow through the combustion chamber to achieve the desired power delivery.
- Dual Overhead Cams Per Cylinder (DOHC) and Variable Valve Timing (VVT): The Revolution Max 1250T features a separate intake and exhaust camshaft on each cylinder. This DOHC design allows independent, variable intake and exhaust valve timing (VVT), each optimized for the front and rear cylinders. VVT contributes to a wider usable speed range and, in addition to torque development, also improves fuel consumption. This enables powerful acceleration from low revs as well as exciting revving and high peak performance. The hydraulic valve clearance compensation contributes to the engine's low mechanical noise. At the same time, this eliminates the need for complex regular maintenance procedures, which in turn saves inspection costs.
- Light metal forged pistons:
- The piston crowns are milled to achieve a precise compression ratio of 12.0:1. The engine achieves its rated performance with fuel of at least 91 octane, but can also handle gasoline with a lower octane number if necessary, with the engine management using a knock sensor automatically preventing damage caused by knocking or ringing.
- A coating on the piston skirt helps reduce frictional resistance.
- For high performance, piston rings with low preload reduce friction.
- The piston rings are coated for increased service life.
- Two spray oil nozzles directed from below onto the piston crowns help dissipate the combustion heat.
- Balancer shafts: Integrated balancer shafts help reduce engine vibrations for increased driving comfort and longevity. The balance shafts are tuned to allow just enough vibration so that the motorcycle feels alive.
- Clutch and transmission: The engine and the six-speed transmission share a common housing in the new Revolution Max. The clutch is operated via a large cross-section Bowden cable for smooth operation with consistent separation and low friction. Their anti-hopping function prevents the engine from over-revving when downshifting and suppresses rear wheel stalling.
Sportster S: instruments
The new Sportster S is equipped with a round TFT display with a 4.0-inch diameter for all display and infotainment functions.
- All display functions are operated both when stationary and while driving using buttons on the control panels on the right and left of the handlebars.
- The low-reflection display is easy to read even in poor lighting conditions. Harley-Davidson has specifically optimized the color scheme and design for the greatest possible reading comfort.
Standard display:
- The large speed display in the middle is framed by a circular tachometer display.
- Turn signals and warning lights appear at the top.
- Pop-up displays for incoming calls and warnings such as “Low Fuel”, “Side Stand Down” or “Low Temperature” (engine not yet at operating temperature) are displayed below the speed display.
Display bike status:
With this display, the driver can view the status information large on the screen, while a smaller speed display appears in the upper area. The status information includes tire pressures, engine temperature and oil pressure, battery voltage and engine management diagnostic codes.
infotainment
The Sportster S display can show infotainment information output from the driver's Bluetooth-compatible mobile device. The motorcycle itself is not equipped with an infotainment system or speakers. Most infotainment features require a separately available Bluetooth headset with speakers inside the helmet
Music
Using a headset, the system can be used to play both stored music files and streamed music from a mobile device. The artist name and song title appear on the display. The rider can scroll and adjust the volume using buttons on the handlebars.
Hands-free function
The driver can control the telephone functions of his mobile device using voice guidance via the headset. Caller data for incoming connections can be shown on the display.
navigation
To navigate, the driver can use the free Harley-Davidson app for iOS and Android, which must first be installed on the mobile device. If the navigation function is activated, an automatically moving road map or turn-by-turn information can be displayed, each supplemented by audio instructions via the headset.
- In road map mode, speed, indicator lights and the like are displayed above the moving map.
- The map can be moved and zoomed using the buttons on the handlebars.
- The Harley-Davidson app's range of functions includes route recommendations, tour planning and recording functions, riding challenges and point-of-interest databases with Harley-Davidson authorized dealers, gas stations, hotels, restaurants, motorcycle events and numerous other attractions.
- A cellular connection is required for the navigation function; the motorcycle itself is not equipped with a GPS receiver. However, if necessary, the driver can create the entire route in advance, download it and save it locally for offline navigation.
- Software updates are performed automatically by the Harley-Davidson app.
Sportster S: Cornering Rider Safety Enhancements
The new Sportster S is equipped with the Harley-Davidson Cornering Rider Safety Enhancements, a package of electronic assistance systems that prove helpful in difficult road conditions and dangerous situations. They are controlled electronically and are based on the latest chassis, braking and drive control technology.
The Sportster S has a sensor system (Inertial Measurement Unit, IMU), which is made up of several inertial sensors on six spatial axes and continuously measures the lean angle while driving. The curve-optimized electronic assistance systems take into account that there is less tire grip available for braking or accelerating in curves than when driving straight ahead, and adapt their control interventions accordingly.
- Cornering Enhanced Antilock Braking System (C-ABS)
ABS prevents the wheels from locking when braking and helps the driver to maintain control during emergency braking while driving straight ahead. It controls the front and rear brakes independently of each other. The cornering anti-lock braking system (C-ABS) also includes the lean angle in this control. When cornering, not all of the traction is available to transmit the braking force. C-ABS automatically takes this into account. The integrated stoppie control (Rear-Wheel Lift Mitigation, RLM) counteracts the lifting of the rear wheel during heavy braking in order to optimally align the deceleration forces with the driver's braking commands.
- Cornering Enhanced Traction Control System (C-TCS)
The TCS traction control prevents excessive slip on the rear wheel when accelerating and thus supports the driver, especially when tire grip is limited, such as in precipitation, suddenly changing road surfaces or on unpaved roads. The C-TCS cornering traction control also takes the current lean angle into account. In the pre-programmed driving modes, the cornering traction control interventions vary in intensity. In the freely programmable driving modes, the driver can preselect the strength of the C-TCS interventions in three levels.
In addition, C-TCS can be deactivated in any driving mode when the vehicle is stationary and the engine is running. When switching to Rain mode, C-TCS is automatically reactivated, but can then be deactivated again. C-TCS can be switched off by pressing a button on the right side of the handlebar.
TCS also includes wheelie control (Front-Wheel Lift Mitigation, FLM), which limits the height and duration of a front wheel lifting when accelerating. The strength of this intervention also differs in the different driving modes, with Rain being the most restrictive mode and Sport/Off-Road having the weakest interventions. When traction control is deactivated, the FLM function is also deactivated.
- Cornering Enhanced Drag-Torque Slip Control System (C-DSCS)
The C-DSCS cornering traction control system is used to reduce excessive slip on the rear wheel and to prevent the rear wheel from locking due to drive influences. This can otherwise occur when abruptly downshifting or closing the throttle grip on slippery roads.
If C-DSCS detects such a driving situation, it automatically adjusts the peripheral speed of the wheel to the driving speed by regulating the motor torque. The system also takes the lean angle into account.
- Tire Pressure Monitoring System (TPMS)
Correct tire pressure is just as important for the handling of the motorcycle as it is for the life of the tires. The tire air pressure monitoring system TPMS shows the tire pressures on the color display and warns the driver if the tire pressure is too low.
Sportster S: driving modes
The Sportster S offers five selectable driving modes that electronically regulate the driving dynamics of the machine and specify the intensity of the electronic interventions. Three of them are pre-programmed and two more can be individually adjusted. Each mode affects power delivery, engine braking, cornering ABS (C-ABS) and cornering traction control (C-TCS).
The driver can select the driving mode using the mode button on the right of the handlebar, with some exceptions both when stationary and while driving. The selected mode is indicated by a symbol on the color display.
With the exception of Road mode, the driver can deactivate the driving modes in the settings menu of the display. The freely configurable modes can only be selected during operation using the mode button once they have been activated in the Settings menu.
- Road mode: The balanced Road mode is intended for everyday use and commuting. The engine offers a less sharp power delivery than in Sport mode, C-ABS and C-TCS intervene earlier. If a malfunction occurs, the driving mode system automatically switches to Road mode.
- Sport mode: Sport mode offers the most unfiltered interaction between driver and machine. The rider experiences the full performance potential of the motorcycle directly and with the highest precision, with unlimited peak performance and all the revving pleasure. C-TCS works at the lowest level that is still sensible for road use and with increased engine braking effect when coasting.
- Rain Mode: This mode is designed for rain or otherwise reduced traction. This makes it ideal for riders who are still getting familiar with the motorcycle. Revving speed and power are significantly reduced in favor of manageable acceleration, as is the engine braking effect, while C-ABS and C-TCS work at the highest level.
- Custom mode: The Sportster S offers two freely programmable driving modes that allow the driver to configure characteristics specifically tailored to their personal preferences or situations. Within certain limits, the driver can set the engine characteristics, engine braking effect and revving as desired, as well as the intensity of the C-TCS and C-ABS interventions. For example, it is possible to combine the powerful power delivery of Sport mode with a reduced engine braking effect.
Further information about the new Harley-Davidson Sportster S can be found at www.harley-davidson.com .