Motul (Racing Brake Fluid) RBF 700 500 ML

Description

Motul RBF700 racing brake fluid boils at 637 deg F dry, 401 deg F wet. It is a glycol-based fluid and meets DOT 4 standards. It is compatible with all vehicles that use DOT 3 or DOT 4 fluid.

Is RBF700 right for you?

We know it’s difficult to choose parts for your car sometimes, so we thought we’d make it easier by offering a concise selection guide for Motul’s brake fluid products.

If you Ride your Bike aggressively on the street or do track days occasionally, Motul’s RBF700 is the fluid for you. It will last at least a year under street driving conditions before needing to be flushed, and has extremely high dry and wet boiling points – much higher than DOT 5.1.

The Details on Motul RBF700 racing brake fluid 

Motul’s RBF700 is an excellent balance between extreme temperature resistance and fluid longevity. Because brake fluid absorbs water over time, and higher temperature resistant fluid absorbs water quicker, it is difficult to find a brake fluid that resists very high temperatures and does not need to be flushed every few months. RBF700 bridges that gap – its dry boiling point is 637 deg F and its wet boiling point is 401 deg F, and it will keep at its dry boiling point for six to twelve months before it starts to fade towards the wet boiling point. For a fluid capable of resisting such extreme temperatures, this is outstanding longevity.

Dry and wet boiling points? That doesn’t even make sense!

Get brake fluid hot enough, and it will “boil”. Although boiling is how it is described, simmering and producing vapour is perhaps a more accurate description. Vapour, unlike fluid, is compressible and can lead to brake fade – on the front or rear – with prolonged heavy use.
Glycol-based brake fluid is hygroscopic (absorbs moisture). Boil it, and it becomes a gas. The gas then cools, and small amounts of water are a by-product of that cycle. Do that enough times, and you end up with hydrated brake fluid (too much water) and soggy brakes, even when they are cool.
When manufacturers quote the dry boiling point for brake fluids, they are talking about the temperature at which their brake fluid, in perfect condition, will boil.The wet boiling point is the temperature at which the same brake fluid will boil when it contains a minimum of 3.7% water.
The bad news for us is that water boils at a lower temperature than brake fluid, which produces micro-bubbles, leading to even worse braking efficiency. All of this is why we should change our brake fluid regularly.
Although there are other chemical differences – which I don’t understand – the wet and dry boiling temperatures are the stand-out differences between the different standards for DOT brake fluids.

We recommend flushing your brake fluid after every race weekend, as once the brake fluid reaches a certain water saturation the water will begin to boil separately, causing the lever to compress substantially more than normal. For more extreme fluids such as RBF700, it is best to change the fluid more frequently to keep the performance benefits of these high temperature fluids.