Harley-Davidson adds traction control

Harley-Davidson is introducing traction control and other electronic rider aids such as hill-start assist and tyre pressure monitors to its 2020 Touring and CVO models.

Last year Harley added traction control to its Trikes and we speculated back in September 2018 that it would soon be arriving in more models.

Now it is also being added to its CVO models as well as the Touring line-up, except for the Road King and Electra Glide Standard. (Click here for more details and pricing on the CVOs.)

We expect it will also be added to the Softail line-up next year.

More than traction control

They call it Reflex Defensive Rider Systems (RDRS) with chassis control, electronic brake control and powertrain technology.

It’s also included in the electric LiveWire which will not be available in Australia until late next year.

Not only does RDRS feature traction control, but also cornering ABS, linked braking, clutch assist to limit rear wheel lock-up, tyre pressure monitors and even assistance to prevent you rolling backward on hill starts!

It sounds more like a BMW than a Harley!

Interestingly, Harley has included this disclaimer for those dumb enough to believe RDRS increases traction or improve rider abilities:

Available traction is determined by the road/tyre interface. The systems bundled into the RDRS are only able to adjust brake pressure or powertrain torque in an attempt to keep the forces at the tyre from exceeding available grip. These technologies do not have the ability to increase grip, or to intervene when the rider has not made a brake or throttle application (e.g. coasting through a corner with the clutch disengaged). RDRS is not a system to directly influence vehicle direction. This is a key difference between motorcycle RDRS and Automotive Stability Control. The rider is ultimately responsible for steering and path corrections.

Features of RDRS include (from the press release):

• Cornering Enhanced Electronic Linked Braking (C-ELB)

This feature applies braking effort to both wheels when the rider uses either the hand lever (front) or foot pedal (rear) brake control, which can help many riders achieve better braking performance. The Electronically Linked Braking (ELB) system provides more responsiveness and allows for more balanced front and rear braking under a wide variety of brake applications. The system provides more linking when the rider is applying heavier braking and reduces or eliminates linking for light braking and low speeds. When linked, applying the front brake lever alone will cause the system to also dynamically apply an amount of braking to the rear. Applying the rear brake pedal alone will cause the system to also apply an amount of braking to the left front calliper. Cornering Enhanced Electronic Linked Braking (C-ELB) takes into account the motorcycle lean angle or Trike lateral acceleration. C-ELB will alter the proportioning of brake pressure between the front and rear brakes when braking while cornering in an attempt to improve the ability of the bike to maintain the rider’s intended path.

• Cornering Enhanced Antilock Braking System (C-ABS)

ABS is designed to prevent the wheels from locking under braking and helps the rider maintain control when braking in a straight-line, urgent situation. ABS operates independently on front and rear brakes to keep the wheels rolling and prevent uncontrolled wheel lock. Cornering Enhanced Antilock Braking System (CABS) is a variant of ABS that takes into consideration the lean angle of a two-wheel motorcycle, or the lateral acceleration of a Trike model. The brake pressure required to limit wheel slip when cornering is typically lower than the pressure required under straight line operation.

• Cornering Enhanced Traction Control System (C-TCS)

The Cornering Enhanced Traction Control System (C-TCS) is designed to prevent the rear wheel from excessive spinning under acceleration when going straight or cornering. C-TCS can improve rider confidence when available traction is compromised by wet weather, a sudden unanticipated change in the surface, or when riding on an unpaved road. The rider may select one of two traction control modes: Standard Mode is optimised for dry surfaces; Rain Mode is optimised for wet surfaces. The system can also be turned off. The action of C-TCS is also tailored when cornering based on lean angle.

• Drag-Torque Slip Control System (DSCS) and Cornering Enhanced Drag-Torque Slip Control System (C-DSCS)

Drag-Torque Slip Control (DSCS) is designed to reduce excessive rear-wheel slip under deceleration, which typically occurs when the rider makes an abrupt downshift gear change or decelerates on wet or slippery road surfaces. When DSCS detects excessive rear wheel slip under deceleration it will adjust engine torque delivery to better match rear-wheel speed to road speed. On models equipped with C-DSCS the action of DSCS may be tailored when cornering, based on detected lean angle (two-wheel motorcycles) or lateral acceleration (Trike models).

• Vehicle Hold Control (VHC)

Vehicle Hold Control (VHC) applies and holds brake pressure when activated and prevents the motorcycle from rolling after the rider has released the brake controls. The primary function of VHC is to prevent the motorcycle from rolling when it is stopped – for example at a stop sign on a hill, in stop-and-go traffic on a slope, or on a steep decline out of a parking structure. VHC is designed to make it easier to ride away with confidence by minimizing the number of controls needed to pull away smoothly. The system applies brake pressure until the rider actuates the throttle and clutch to pull away. VHC may also be engaged when the motorcycle is stopped on a flat surface if the rider wants to maintain position without applying pressure to a brake control.

The rider activates VHC by momentarily applying extra pressure to either the front brake hand lever or the rear-brake foot control after the motorcycle has come to a complete stop. If rider brakes very hard to a stop, and holds the brake pressure after stopping, VHC may also set without any added squeeze. A VHC indicator light will illuminate to confirm that the rider has activated VHC, and the ABS system will hold brake pressure after the rider releases the brake control. VHC is disengaged automatically as the rider begins to pull away from a stop, or if the rider applies and releases either brake control.

VHC is not to be used as a parking brake, so it will also disengage if the rider lowers the side stand (on models with a side-stand sensor, not a feature in all markets) or shifts into neutral on models without a side-stand sensor, or if the engine is turned off. In most situations after five minutes the indicator light will flash and the VHC will release if there is no rider action.

• Tyre Pressure Monitoring System (TPMS)

TPMS alerts the rider to low tire air pressure. Maintaining proper tire air pressure is important both for vehicle performance and tire life. The TPMS displays current front and rear tire pressure on the Boom! Box GTS screen (or on the odometer on Road King models) and displays an indicator to alert the rider when tire pressure is low, and the pressure should be checked.

RDRS for Trike Models: Harley-Davidson Freewheeler and Tri Glide Ultra models are equipped with Trike-specific Reflex Defensive Rider Systems with Cornering Enhanced Electronic Linked Braking (C-ELB), Cornering Enhanced ABS (C-ABS), Cornering Enhanced Traction Control System (C-TCS) and Cornering Enhanced Drag-Torque Slip Control System (C-DSCS). The CVO Tri Glide model will add TPMS to the Trike-specific Reflex Defensive Rider Systems.