possibly fatal technical issue (brake fluid)

[wrightme43]

Originally Posted by VEGASRIDER

Hey Steve, it seems you are very knowledgeable in this area than the average person as well as having the confidence to change the fluids. How bout creating a "How to" thread on changing the brake fluids?

Here you go Vegas and I will make it a sticky too.

http://www.fz6-forum.com/forum/how-t...nes-fluid.html (How To, RR, Front Pads, Lines, Fluid.)

[Nelly]

Originally Posted by sportrider

thats funny

You have all those videos of him (FZ6), lets just remember him the way he was.

Nelly

Originally Posted by wrightme43

No I disagree. Moisture, road grime, and brake dust does get past the seals. I have done a insanely large number of brake jobs, with fluid changes. However I will go now and find data to back up my statements.

Well, don't bother looking for it in the owner's manual or shop manual because it isn't there. Also, I guarantee you you have never done a fluid change on anything with an ABS computer unless you somehow or another managed to find your way to a pressure bleeder. Brake fluid is some amazing stuff and you would be very hard pressed to find anything supporting the fact that an accident occurred due to a brake failure caused by fluid with too many miles on it. Think of the millions of bikes and cages that are on the road that have never had the fluid changed or the licensed brake shops that are out there doing brakes that never change fluid and only added as necessary. The fluid goes down in the master cylinder reservoir because the piston in the caliper moves out as the pads wear. When you replace the pads and push the piston back in the fluid moves back into the reservoir as opposed to remaining in the caliper. If it doesn't leak it has no place to go and I have yet to observe brake fluid evaporate off. I have however seen foreign material introduced into the system from improper maintenance. To each there own but fluid changes are a waste of time and money unless there is a problem that warrants the change and this is why it isn't done throughout the industry.

[wolfc70]

Originally Posted by sportrider

6-23 of the owners manual states DOT 4. do not use DOT 3 or you could have break failure. these fluids don't mix!!!

Actually they do as both are polyethylene glycol. As is DOT 5.1. DOT 5 is silicone and will not mix with anything and is not compatible with other non DOT 5 seals. DOT 3 has a boiling point of 401 F and DOT 4 has a boiling point of 446 F. Do not forget that all polyethylene glycol based fluids are hygroscopic, meaning they absorb moisture from the air and moisture lowers the boiling point considerably. Girling brakes used a mineral oil as those systems had natural rubber seals.

[CanadianFZ6]

Originally Posted by lonesoldier84

I bought it at 3,999km

she now has just over 9,950 km.

For maintenance i had done nothing brake related although twice during this phase i had the bike in a shop and they checked brakes one of the times while it was there that was closer to the 8,000km mark though when they did that.

i based the fact I had no brake fluid on the fact that i could not see the fluid. I am VERY confident that it used to be yellow. Did it change colour?!? I cant see it with a flashlight right now but thats cuz theres lots of reflection when i hold it close. when i hold it further I am not sure if it is a clear liquid or if it is empty. I have not opened anything to check.

And as for checking the brakes and such myself. I will be doing that tomorrow if you say it is not in fact that difficult. I have purchased a magical amazing book written wonderfully with tons of very helpful pictures. It is about moto-maintenance and such. Also ive got the yamaha manual for the 2006 fz6. Armed with all of this I will surely succeed. If I have any questions, do not fear I will not hesitate to post (as I am a spam-bot anyway why stop now?!? mwahaha )

thanks again all. this forum never ceases to amaze me with how wonderful it is. and i dont just mean for getting info. It is just amazing. I am on a handful of other very large forums. and they all get blown away by this one to the point i rarely visit the others anymore.

Jeez, yes, it's amber... now go get a philips screwdriver, level the reservoir and handlebars and take the damn top off the reservoir and look in... takes 30 seconds to do. Put this to rest once in for all. If the brake pads are still good, just fill it to the line with dot 4 fluid..... I can change the brake pads and bleed the brake fluid with just simple tools (socket and a few small wrenches) in about an hour. It is actually very easy to do.... Maybe Steve (Wrightme43) will do a write up.... Don't get any brake fluid on paint or plastic on your bike....

[wrightme43]

Originally Posted by HavBlue

Well, don't bother looking for it in the owner's manual or shop manual because it isn't there. Also, I guarantee you you have never done a fluid change on anything with an ABS computer unless you somehow or another managed to find your way to a pressure bleeder. Brake fluid is some amazing stuff and you would be very hard pressed to find anything supporting the fact that an accident occurred due to a brake failure caused by fluid with too many miles on it. Think of the millions of bikes and cages that are on the road that have never had the fluid changed or the licensed brake shops that are out there doing brakes that never change fluid and only added as necessary. The fluid goes down in the master cylinder reservoir because the piston in the caliper moves out as the pads wear. When you replace the pads and push the piston back in the fluid moves back into the reservoir as opposed to remaining in the caliper. If it doesn't leak it has no place to go and I have yet to observe brake fluid evaporate off. I have however seen foreign material introduced into the system from improper maintenance. To each there own but fluid changes are a waste of time and money unless there is a problem that warrants the change and this is why it isn't done throughout the industry.

OK if you insist.

Brake Fluid Change Interval - ShopForum

and another.

VWvortex Forums: Brake Fluid Change Questions

and again

Brake fluid: To understand the importance of good brake fluid it is necessary to understand how a hydraulic system works. Fluids are non-compressible. This means when you step on the brake pedal the pressure you’re applying is distributed equally (regulated by some valves) throughout the system. Step on the brake pedal and you are pressing on the wheel cylinders and the calipers.
This whole system goes out the window if any gas (including air or water vapor) gets into the system. Gas compresses. When this situation occurs, stepping on the brake pedal compresses the gas instead of putting pressure on the brake parts.
Brake fluid is pretty amazing stuff. The components in a brake system can reach a temperature of 5,000° and even at that temperature, good brake fluid doesn’t boil. This amazing stuff does have one weakness — it absorbs water. When it has absorbed too much water, the water will precipitate out and then can boil, or change into gas. This is one of the major causes of brake fade coming down a hill or a mountain. The water can also create rust inside the brake system, leading to a failure of the brake wheel cylinders and calipers. Brake fluid also gets dirty. It has been estimated that as much as 80% of brake master cylinder failures are due to dirty brake fluid. The estimated interval for changing brake fluid, under normal use, is every two years.

But wait thats not all.

VW Brake Fluid - ATE VW Brake Fluid - VW Brake Flush


Whats up with this. Everybody says HEY CHANGE YOUR BRAKE FLUID EVERY TWO YEARS.

Why? Because it absorbs up moisture, and trash gets past the seals and it gets in the caliper.

If you dont want to thats fine but dont be telling everyone that its wrong to do so. It is right to do so.


On the other. Yes I have used a pressure bleader. Give me a break. Mityvac works too.

If you want I can go on. The recomeneded change interval is two years. It has been and will be. We live in severe service land where the consequence of failure is so high the cost of a 6$ bottle of fluid is a neglible expense compared to the price of brake problem.

I know what I am talking about Charlie. If you dont want to change your fluid thats fine, but dont tell me its wrong when I know its right.

[steveindenmark]

Originally Posted by sportrider

6-23 of the owners manual states DOT 4. do not use DOT 3 or you could have break failure. these fluids don't mix!!!

You are correct here.

Dot 3 will eat away at your rubber seals.

These levels should be checked on a regular basis. I look at mine at least once a week. it takes all of 5 seconds to do the whole job.

I think there are also tell tale marks on both sets of brakes.

Steve

[wrightme43]

Here is one more.

Understanding Brake Fluid - RPMnet.com tech articles - by AFCO racing

3 and 4 and 5.1 are compatable with our seals. Dot 5 is silocone and not compatable.

Sorry ^^^^ this is wrong, or at least not 100% right. We can use 4 and 5.1, probley 3 but it may not be ok with the seals. Our call out is of course 4 or better.

[wrightme43]

Here is one more just in case.

StopTech : Balanced Brake Upgrades


Or you could hunt up a book.

Its called
Engineer to Win (or how to build winners that dont break)
By Carrol Smith.

It explains metalurgy, fluids, fasteners, design, stress, and basicly the stuff that is overlooked by most.
Why does one racer finish in front and another finish behind? Its the one that KNOWS his/her stuff is right. Confidence comes from having everything being the best it can be.

[DefyInertia]

All I know is that everytime I've changed out fluid on an older bike, the fluid that came out was nasty and the braking performance improved significantly after putting the new fluid in....but that's the real nasty stuff.

In a typical situation...brake fluid that has been left unchanged and obsorbed a lot of moisture (everyone knows brake fluid sucks up moisture) will still perform just fine so long as you don't really put it to the test. If you're really using your brakes, like at the track, pushing it on a twisty road, stunting, or going down hill for super long, your brakes will fade when the fluid gets too hot (too much moisture)....this is very basic and can't be denied. This is why brake fluids are rated at their "wet boiling point".

On the other end....people who really beat on there brakes change the fluid more than once per race season....they are looking for TOP performance and obviously don't want any more fade than necessary during any given race.

Doesn't the manual say the lines should be changed out after four years? I know it's just a precaution but.... Bottom line is, you can get away with a whole lot, especially if you don't work the brakes real hard, but like anything else the amount of maintenance that I would consider prudent depends on the use...at some point use should be replaced with time (for example: "it's been four years, might as well spend $100 to change the front lines, inspect everything, and flush the fluid").

Now that I really think about it, I seem to remember my original fluid being amber...which is odd if you ask me. I just changed the fluid on a friends 2002 SV650 and man was that stuff gross...brown, hazy, and with a spongy lever especially after doing repeated stoppies....we put in new fluid only and things greatly improved (6 year old bike that probably had the original fluid in there....bike was fine but peak performance was definitely compromised).