Motul RBF 660 Factory Line Dot 4 Brake Fluid 500ml

Motul RBF 660 Factory Line DOT 4 Brake Fluid 500ml – Extreme High-Temperature Racing Brake Fluid

Motul RBF 660 Factory Line is a high-performance DOT 4 brake fluid developed for extreme braking temperatures and demanding motorsport use.

With an exceptionally high dry boiling point of 325°C / 617°F and wet boiling point of 204°C / 400°F, RBF 660 is designed to maintain braking consistency when conventional road-focused fluids may begin to struggle.

Suitable for compatible hydraulic brake and clutch systems requiring a non-silicone synthetic fluid, RBF 660 is particularly well suited to track cars, race cars and high-performance braking systems exposed to repeated heavy braking.

Why Choose Motul RBF 660?

Motul RBF 660 is designed for vehicles operating at very high brake temperatures.

It is particularly suited to motorsport environments where aggressive pads, large braking systems and limited cooling airflow can create extreme thermal loads.

Key benefits include:

• 325°C dry boiling point
• 204°C wet boiling point
• DOT 4 specification
• High-performance synthetic formulation
• Non-silicone brake fluid
• Suitable for hydraulic brake systems
• Suitable for compatible hydraulic clutch systems
• Designed for extreme racing brake temperatures
• Suitable for high-performance brake systems
• Strong resistance to vapour lock and fluid boiling

Key Features

• Motul RBF 660 Factory Line
• 500ml bottle
• High-performance DOT 4 brake fluid
• Dry boiling point: 325°C / 617°F
• Wet boiling point: 204°C / 400°F
• Non-silicone synthetic formulation
• Suitable for compatible hydraulic brake systems
• Suitable for compatible hydraulic clutch systems
• Developed for extreme braking temperatures
• Suitable for racing applications
• Designed for high-performance carbon and ceramic braking systems
• Ideal for repeated heavy braking

325°C Dry Boiling Point

The dry boiling point of Motul RBF 660 is an exceptional 325°C / 617°F.

This gives the fluid substantial thermal headroom during periods of intense braking.

A high dry boiling point is particularly important in applications involving:

• Track days
• Motorsport
• Endurance racing
• Time Attack
• Repeated high-speed braking
• High-grip tyre setups
• High-powered vehicles
• Performance brake kits

The greater the braking energy being generated, the more important fluid temperature resistance becomes.

204°C Wet Boiling Point

Motul RBF 660 has a wet boiling point of 204°C / 400°F.

Brake fluid naturally absorbs moisture from the atmosphere over time, which reduces its boiling temperature.

A strong wet boiling point helps maintain performance as the fluid ages, although track and race vehicles should still have brake fluid replaced regularly.

Designed for Extreme Brake Temperatures

RBF 660 is specifically developed to resist the very high temperatures generated by competition braking systems.

This includes applications using:

• Carbon brake systems
• Ceramic braking components
• Motorsport brake pads
• Large multi-piston calipers
• Two-piece floating discs
• Big brake kits
• Limited brake cooling airflow

In these environments, brake fluid can be subjected to much higher temperatures than it would normally experience during everyday road driving.

Helps Resist Vapour Lock

When brake fluid reaches its boiling point, vapour can form within the hydraulic system.

Vapour is compressible, unlike liquid brake fluid.

This can result in:

• Soft brake pedal
• Increased pedal travel
• Reduced braking consistency
• Brake fade
• Loss of confidence under repeated braking

The extremely high boiling point of RBF 660 helps reduce the risk of vapour formation during severe use.

Designed for Racing Brakes

Motul RBF 660 is specifically suited to high-performance braking systems that generate extreme temperatures.

This makes it particularly appropriate for:

• Race cars
• Track-focused performance cars
• Clubsport builds
• Time Attack vehicles
• High-powered cars
• Motorsport applications
• Cars with racing brake pads
• Cars with big brake kits

For dedicated circuit use, RBF 660 provides a level of thermal performance considerably beyond conventional road brake fluids.

Suitable for Hydraulic Brake & Clutch Systems

Motul RBF 660 can be used in compatible hydraulic:

• Brake systems
• Clutch systems

The system must be designed for a non-silicone synthetic brake fluid.

Always check the vehicle manufacturer's requirements before use.

RBF 660 vs Standard DOT 4

Although RBF 660 is a DOT 4 brake fluid, its performance is aimed at a very different type of application than a conventional road DOT 4 fluid.

Standard DOT 4 fluid is designed primarily for everyday road braking systems.

RBF 660 is developed for:

• Much higher brake temperatures
• Repeated heavy braking
• Motorsport use
• Track cars
• High-performance braking systems

Its 325°C dry boiling point provides substantially greater thermal resistance than typical road-oriented DOT 4 fluids.

RBF 660 vs RBF 600

Both RBF 600 and RBF 660 are high-performance Motul Factory Line brake fluids.

RBF 600 offers:

• 312°C dry boiling point
• 205°C wet boiling point

RBF 660 offers:

• 325°C dry boiling point
• 204°C wet boiling point

RBF 660 therefore provides a higher dry boiling point, making it particularly attractive for applications where peak brake temperatures are especially high.

RBF 600 remains an excellent option for fast-road and track-day use, while RBF 660 moves further toward dedicated high-temperature track and motorsport applications.

Performance Brake Kit Compatibility

Motul RBF 660 pairs well with high-performance braking hardware such as:

• AP Racing calipers
• XC3 Engineering BTCC brake kits
• Multi-piston big brake kits
• Two-piece brake rotors
• Racing brake pads
• Braided brake lines

Brake fluid is an important part of any performance braking setup and should be selected to match the temperatures and demands created by the rest of the system.

Track & Motorsport Use

RBF 660 is especially well suited to vehicles that see:

• Frequent track days
• Sprint events
• Time Attack
• Clubsport use
• Circuit racing
• Endurance use
• Repeated high-speed braking

Vehicles operating in these environments can generate brake temperatures far beyond those seen in normal road use.

Brake Fluid Maintenance

Brake fluid absorbs moisture over time.

As moisture content rises, the boiling point falls.

For track and motorsport vehicles, fluid should generally be inspected and replaced more frequently than on a road-only car.

Fresh fluid helps maintain:

• High boiling resistance
• Consistent pedal feel
• Reliable hydraulic pressure
• Strong braking performance
• Predictable response under load

500ml Bottle

Motul RBF 660 is supplied in a 500ml bottle.

The amount required depends on the vehicle and braking system.

A complete fluid flush may require more than one bottle depending on the size and design of the hydraulic system.

Professional Installation Recommended

Correct bleeding is essential when replacing brake fluid.

Any air remaining within the hydraulic system can compromise pedal feel and braking performance.

Professional servicing is recommended if you are unfamiliar with brake bleeding procedures or high-performance braking systems.

Important Information

Always check that a non-silicone DOT 4 fluid is suitable for your vehicle before use.

Brake fluid is safety critical and should be kept free from contamination.

Avoid contact with:

• Water
• Oil
• Dirt
• Incompatible hydraulic fluids

Brake fluid can also damage paintwork, so spills should be dealt with immediately.

Once opened, keep the container tightly sealed to minimise moisture absorption.

Ideal For

Motul RBF 660 Factory Line is particularly well suited to:

• Race cars
• Track-day cars
• Time Attack builds
• Clubsport vehicles
• Performance road cars seeing extreme brake temperatures
• Cars with big brake kits
• High-powered vehicles
• Motorsport braking systems
• Carbon and ceramic racing brakes
• Vehicles running high-grip tyres

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