Was riding the Blue Ridge Parkway on Saturday. Was a blast, most of the leaves were already down, so hardly any traffic. Oh yeah it was cold too. Anyway had the wife on the back and was zipping along pretty good. Decided to exit the Parkway at Afton mountain. Coming down 250 decided to jump on Route 6 which twists and turns down the mountain really steep. After a couple of wild turns hard on the brakes, my rear brake went out completely. My wife could tell there was something wrong, I used the engine and the front brake to come to a stop. Turned around went back up the mountain and got back on 250 where it's pretty much a gradual descent.
After a while I managed to pump the brake back up. Must of overheated the brake fluid and foamed it up.
My question is, after 2 more days of riding on flat roads, the brake seems to be working fine. Should I be concerned and replace that fluid? I put Dot 5 synthetic in the last time I changed the pads.

 

I've never experienced the loss of brakes on a bike but I did have that happen to me whiled coming down Tioga Pass (Yosemite) and my 8,000 lb. trailer behind my Suburban pushing me. It was a very scary ride when near the bottom I realized my brakes were going out. About crapped my pants as I finally came to a stop, halfway through the intersection at the bottom of the mountain.

Anyway, after a brief period, the fluid cooled down and I never had any further incident. However I did change out the fluid shortly afterward. Since you are on a bike and safety is so much more of a concern, I would advise you change out that fluid. Once it boils I believe it loses some integrity (JMHO). I wouldn't take the chance myself.

 

I agree 100%. Brake fluid, even dot 5, is cheap. Flush it.

 

First I heard of boiling the fluid, guess that's why it turns dark after awhile? How common is that...been riding for a long time and never had it happen to me....how about the rest of you guys?

 

As suggested by others, it sounds as though your brake fluid reached its boiling point. I would completely change the brake fluid. Below is a list of boiling points for brake fluids.


Boiling points for common braking fluids [1]
Dry boiling point Wet boiling point
DOT 3 205 °C (401 °F) 140 °C (284 °F)
DOT 4 230 °C (446 °F) 155 °C (311 °F)
DOT 5 260 °C (500 °F) 180 °C (356 °F)
DOT 5.1 270 °C (518 °F) 190 °C (374 °F)

Also, here is a good site to read regarding brake fluid and its life span.
http://www.aa1car.com/library/bfluid.htm

 

Wow, I had no idea you could boil fluid like that. I know my rear fluid is original.....I'm flushing it just to be safe!

 

http://ezinearticles.com/?The-Import...cks&id=1712629

Long read but it may clear up some mis conceptions about brake fluids .

 

Maybe I'm missing something here? When going down a long, steep grade, I use the engine (lower gear) more than anything else to keep me at a safe, steady speed. Why would anyone "ride" the brake/s in that situation??

 

the great brake systems we have the past 30 years leave many operators forgetting the basics.

DON"T ride the brakes.

hot brakes don't stop the vehicle.

2.) when you have a problem...STOP !

don't turn around and go up the hill.


Once you experience a problem, have the brakes inspected and flush the fluid.

( does that bike require dot 5 or dot 4-? different fluid for some years)


I drive a lot of antiques and classics, the operator just has to be aware of how the systems are responding to conditions.


Mike

 

Bingo!!!

This is a perfect example of why it's good to have at least a basic understanding of how your bike (or anything for that matter) works.

The only way your brake fluid should ever get anywhere near boiling is if you're on a racetrack, or are riding like you are on one. And even then you should be able to feel the brakes starting to fade well before a complete failure, indicating that you need to lighten up on the brakes.