The front brake on your motorcycle provides at
least 70 percent of your braking power! 8O Therefore, it is vital to properly maintain your front brake.
You should regularly inspect your front brake rotor, and brake pads. It is also important to change you brake fluid on a regular basis.
As with most liquids, brake fluid does not compress much under pressure. Therefore when you squeeze your brake lever, the brake fluid transfers the pressure generated at the master cylinder to the front brake caliper, compressing the brake pads against the brake rotor. However, unlike most liquids, brake fluid is a special liquid, designed with special properties.
Brake fluid is designed to have a high boiling point. When you apply the brakes, the friction between the brake rotor and the brake pads generates a lot of heat, and some of this heat is transferred to the brake fluid. When a liquid boils, it becomes a gas; unlike liquids, gasses
will compress under pressure. :( Therefore, if your brake fluid starts to boil, your brake lever will become mushy, and you will not stop as fast.
Besides having a high boiling point, brake fluid also contains anti-corrosion additives, and these additives help prevent your brake system from rusting.
Brake fluid deteriorates with time, and usage. The main culprit causing this deterioration is moisture.
Brake fluid is hygroscopic, which means it absorbs moisture from the atmosphere. Over time, moisture enters the brake fluid via the permeability of the brakes hoses, brakes seals, the master cylinder cap, et cetera.
Water has a much lower boiling point than brake fluid. Therefore, old brake fluid contaminated with water will boil faster than fresh brake fluid. Also, water degrades the anti-corrosion additives in the brake fluid, promoting rust. :(
As brake fluid deteriorates, it changes color. Fresh brake fluid is clear, but contaminated brake fluid becomes progressively darker as the contamination increases. If you don’t race, you are probably safe changing your brake fluid once a year. However, a change in color is the best indication you need to change your brake fluid.
If you want your brakes to perform well, and not be damaged by moisture, you should change you brake fluid on a regular basis.
The following link points to a PDF file containing a lot of interesting information regarding the properties of brake fluid.
http://www.mightyautoparts.com/pdf/articles/tt136.pdf
In my next post I will tell you how to change your brake fluid.
Spud