100% Synthetic Racing Fluid – DOT 4
Very high boiling point : 328°C / 622°F
For hydraulic actuated brake and clutch systems
TYPE OF USE
All types of hydraulic brake and clutch actuators requiring non-silicone synthetic fluid.
Specially designed to resist to extreme temperature generated by racing carbon and ceramic brakes
allowing minimizing air entrance for brake cooling.
Can be also used with conventional steel discs and clutch systems actuators.
Widely exceeds DOT 3, DOT 4 and DOT 5.1 standards (except for DOT 5.1 viscosity at - 40°C).
PERFORMANCE
STANDARDS : FMVSS 116 DOT 4 / SAE J1703
Extreme thermal resistance and stability :
Very high boiling point (328°C / 622°F), superior to conventional DOT 5.1 fluids (260°C / 500°F mini)
and DOT 4 (230°C / 446°F mini)
Enables effective brake even in extreme conditions.
Better aerodynamic performance by reducing air entrance for brake cooling on cars.
Efficient when rainy:
Very high wet boiling point (204°C / 399°F) superior to conventional DOT 5.1 non-silicone base fluid
(180°C / 356°F mini) and DOT 4 (155°C / 311°F mini) enables to keep efficient braking in wet
conditions.
Brake fluids tend to absorb humidity from the air, which reduce boiling point and increase the risk to get
to “vapor lock” phenomena.
The wet boiling point is measured by humidifying the product with about 3.5 % of water.
RECOMMENDATIONS
Avoid mixing with polyglycols based brake fluid.
Do not mix with silicone (DOT 5 silicone base) or mineral base fluids (LHM).
Store brake fluid in its original container, tightly closed to prevent moisture absorption.
Aggressive chemical product if contact with hands, paint or varnish.
If skin contact, rinse thoroughly with water.
PROPERTIES
100% synthetic fluid, polyglycol bases.
Colour Amber
Dry boiling point 328 °C / 622 °F
Wet boiling point 204 °C / 399 °F
Viscosity at -40 °C (-40 °F) 1698 mm²/s
Viscosity at 100 °C (212 °F) 2.59 mm²/s
MOTUL RBF 660 Factory Line
Specification limits
TEST Unit DOT 3 DOT 4 DOT 5.1 RFB 660
Dry boiling point °C >205 >230 >260 328 (622°F)
Wet boiling point °C >140 >155 >180 204 (399°F)
Viscosity at - 40°C (- 40°F) mm²/s <1500 <1800 <900 1698
Viscosity at 100°C (212 °F) mm²/s >1.5 2.59
pH 7-11.5 7.15
Effect on rubber SBR (Styrene-butadiene)
Volume change at 70°C (70 hours) mm 0.15-1.4 0.76
Softening (IRHD) 10 max 4
Disintegration no no
Volume change at 120°C (70 hours) mm 0.15-1.4 1.05
Softening (IRHD) 15 max 7
Disintegration no no
Evaporation
Loss at 100°C weight % 80% max 50
Fluidity and appearance at low temperature
Appearance at -40°C No freezing OK
Bubble time s 10 max OK
Appearance at -50°C No freezing OK
Bubble time s 35 max OK
Water tolerance
Appearance at -40°C clear OK
Flow time s 10 max OK
Appearance at +60°C clear OK
Sedimentation % 0.15 max OK
Anti-corrosion properties: Weight variation
Tinned iron mg/cm² 0.2 max 0.03
Steel mg/cm² 0.2 max 0.01
Aluminium mg/cm² 0.1 max 0.02
Cast iron mg/cm² 0.2 max 0.1
Brass mg/cm² 0.4 max -0.04
Copper mg/cm² 0.4 max -0.05