Brake fade
- Thread starter bobsr3
- Start date
TOMCAT
Rage against the machine
- Joined
- Jan 9, 2011
- Messages
- 9,259
- Location
- ALBANY - Western Australia
- Ride
- 2009 RIII Standard - 2008 Speed Triple -1995 900 T'Bird
I've had my rear brakes disappear on me ... on a mountain range after some pretty spirited riding.. pulled up , had a couple of cigarettes ( important even if you are a non-smoker) got back on and continued on my way. Never happened since ... been riding just as hard but ... 
go figure !!!
go figure !!!bobsr3
Standard Bore
Thanks for all the info but I have been riding motorcycles since I was 10 years old and I know to use the front brake more than the rear and that is what bothered me. I usally dont use the rear brake at all or only when I need to stop extremely fast which is also a bad habit. I also have been really bad over the years about changing out the brake fluid but this is the 1st time I have ever had this type of failure in my brakes and I grew up in the mountains of West Virginia. Please hold the jokes about WV, I have heard them all . I guess the system just needs new fluid so I going to change it out and HOPE that the problem doesn't return. I doesn't seem to be a wide spread problem by the responses I got and again thanks for all the responses to my question.
. I guess the system just needs new fluid so I going to change it out and HOPE that the problem doesn't return. I doesn't seem to be a wide spread problem by the responses I got and again thanks for all the responses to my question.
This post is old, but it happened to me today. Went for the twisties (three days in a row), and today that rear brake made my underwear brown; after 10 or so miles of twisties, he decided to not work and went on strike. Gladly we were arriving to our destination; let it sit for almost an hour and when I started riding again, pedal was working ok. But 30 to 40 minutes after, twisties again, that pedal started flooring again. So, what I understand is that I need to change my brake fluid? No leakages, no nada. Should I look into something especifically?
Thanks for your replies.
Thanks for your replies.
cr0ft
Living Legend
What happens when the pedal bottoms out is that the brake fluid boils. Bubbles form and suddenly pushing on the pedal does nothing (as hydraulics have to be free of air or gases so the pressure of the pedal is moved to the brake caliper). It's happened to me once, and that was when I was nervously overusing my rear brake going down what seemed like a sheer wall in Norway, the disc was practically red hot. If you use the brake to the point where the disc gets that hot, you can generate enough heat to make the brake fluid boil.
This boiling happens much sooner with impure and water-laced brake fluid, and since brake fluid is hygroscopic (absorbs moisture from the atmosphere) that's almost unavoidable, so changing the brake fluid regularly is recommended.
However, you can still achieve temperatures high enough to make even clean brake fluid boil.
Personally, I think using sharp applications of braking for as brief periods as possible and then staying off the brakes entirely until they cool might make sense instead of long drawn out partial braking, and use the front brakes properly, there are two discs up ahead there to share the generated heat from the friction. The rear brake is just there to add the 10% extra braking, it's not your main brake.
The Rocket is heavy. When you need to slow down a moving mass, you transfer the energy in that movement into the brakes. When the object is heavy and moving quickly, it's a lot of energy, which will cause a lot of heat to get generated. It's easier to stop a feather-light supersport, and they still have giant brake discs. So I can definitely see why an overused rear brake can get hot.
This boiling happens much sooner with impure and water-laced brake fluid, and since brake fluid is hygroscopic (absorbs moisture from the atmosphere) that's almost unavoidable, so changing the brake fluid regularly is recommended.
However, you can still achieve temperatures high enough to make even clean brake fluid boil.
Personally, I think using sharp applications of braking for as brief periods as possible and then staying off the brakes entirely until they cool might make sense instead of long drawn out partial braking, and use the front brakes properly, there are two discs up ahead there to share the generated heat from the friction. The rear brake is just there to add the 10% extra braking, it's not your main brake.
The Rocket is heavy. When you need to slow down a moving mass, you transfer the energy in that movement into the brakes. When the object is heavy and moving quickly, it's a lot of energy, which will cause a lot of heat to get generated. It's easier to stop a feather-light supersport, and they still have giant brake discs. So I can definitely see why an overused rear brake can get hot.
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As a matter of fact, I didn't use the brakes on my way back (up and down again) and still after a while it happened again. Already bought new brake fluid to replace. And here comes the question? The how to bleed the full line is by just open the relief valve in the back and press the pedal the get all the fluid out and replace with new fluid?
