Brake system (Harley V-Rod VRSCA)

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General information

The rear brake pedal controls the rear wheel brake and is located on the right side of the motorcycle. The brake pedal of the rear wheel is controlled by the right foot.

The front brake lever controls the front wheel brake and is located on the right side of the handlebar. The hand lever is controlled by the fingers of the right hand.

Warning! Do not insert your fingers between the hand control lever and the steering wheel grip. Incorrect hand position can impair control of the lever, causing the motorcycle to lose control, which can result in serious injury or death.

Some models are equipped with a brake system that prevents wheel locking.

Braking system without wheel lock prevention

In order not to block the wheels, you need to brake gradually and evenly. For best results, brake smoothly with both the front and rear brakes at the same time.

Warning! Do not brake too hard to avoid locking the wheel. If even one wheel is locked, the motorcycle may lose control, which could result in serious injury or death.

Braking system that prevents wheel locking (ABS)

The Harley-Davidson anti-lock braking system helps the rider maintain control when braking in dangerous situations. ABS operates independently of the front and rear brakes, it ensures constant wheel movement and prevents uncontrolled wheel locking - both on dry cobbled streets and on slippery roads - covered with gravel or leaves, or wet with rain.

ABS system: principles of operation

ABS uses sensors to measure the speed of the motorcycle's front and rear wheels. If the system detects that one of the wheels is decelerating too quickly (which indicates the possibility of blocking), or the deceleration rate is not consistent with the criterion stored in memory, the ABS system begins to react. The system quickly opens and closes valves that modulate the brake pressure applied by the driver (based on the forces applied by the driver to the front and rear brake levers). When the ABS system is in operation, it electronically performs the equivalent of manually pumping the brakes, with pumping cycles performed up to 7 times per second.


The driver can detect ABS operation by feeling a slight pulsation in the handbrake lever or rear brake foot pedal. The pulsating sensation may be accompanied by a characteristic clicking sound made by the ABS module. Both of these phenomena indicate normal operation. See table 18.

ABS system: operation

Although ABS provides benefits during emergency braking, it does not replace the rules for safe motorcycle riding. The safest way to stop a motorcycle is to brake smoothly while it is upright, using the front and rear brakes.

Harley-Davidson's ABS is an assistance system. In an emergency braking situation, brake pressure is included in all ABS events. Do not change the braking pattern, do not brake intermittently. The wheels will not lock until the end of the ride, when the motorcycle's speed has dropped to 4 mph and the ABS system is no longer needed.

Warning! ABS cannot prevent the rear wheel from locking due to engine braking being applied. ABS should not be used when cornering or on uneven or loose roads. If even one wheel is locked, the motorcycle may lose control, which could result in serious injury or death.

ABS system: tires and wheels

Motorcycles equipped with ABS must always use tires and wheels identical to the original ones. ABS monitors wheel speed using separate sensors mounted on the wheels. If the wheel diameter or tire size changes, the wheel speeds may also change. This may degrade ABS calibration and have a negative impact on its ability to detect and prevent wheel lockup. Significantly lower tire pressure can also have a negative effect.

Table 18. Signs of ABS system operation and conditions corresponding to them

SIGN	CONDITION
Pulsation of the brake lever or pedal when ABS is activated	Normal phenomenon
Clicking sounds when ABS activates	Normal phenomenon
ABS lamp flashing	Normal phenomenon - key turned to IGNITION position - speed less than 5 km/h (3 mph).
Braking is jerky	Normal - noticeable when braking with one brake (front only or rear only). As a result, deceleration may decrease, which may be due to potholes and cracks in the road surface, engine braking (at high engine RPMs, the rear wheel slows down slower than the front), hard braking at low speed and other conditions. This occurs because the ABS system modulates brake caliper pressure to prevent the wheels from locking.
The rear brake pedal is hard at times	Normal phenomenon - observed when braking the engine (At high engine RPMs the rear wheel decelerates more slowly) or when shifting to a lower gear, the ABS may engage. If the rear brake is applied at the same time or immediately afterwards, the ABS may close the valve to prevent pressure from being transferred to the rear brake. This occurs because the ABS system modulates brake caliper pressure to prevent the wheels from locking.
Tires squeal	It is normal that, depending on the road surface, the tires may squeal, but the wheels will not lock.
Black stripes on the pavement	It is normal that, depending on the road surface, the tires may leave black streaks, but the wheels will not lock.
Wheel locking at low speed	Normal - ABS will not engage the front wheel at speeds less than 3 mph (5 km/h) or wheelie at speeds less than 5 mph (8 km/hour)

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Article about repair motorcycles «Harley V-Rod VRSCA» (2002-2006): «Brake system»: https://motoinstruction.ru/en/Harley/V-Rod/VRSCA/owner/devices/110410 <a href="https://motoinstruction.ru/en/Harley/V-Rod/VRSCA/owner/devices/110410">Brake system</a> - article about repair motorcycles «Harley V-Rod VRSCA» (2002-2006) from section «Control devices». [url=https://motoinstruction.ru/en/Harley/V-Rod/VRSCA/owner/devices/110410]Brake system[/url] - article about repair motorcycles «Harley V-Rod VRSCA» (2002-2006) from section «Control devices».