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How often do you change your brake fluid on how much does it really affect performance and wear on components, DOT3 or 4?  

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At least 2x per year!

 

  DOT 5.1

 

I hate loosing my brakes when the fluid gets too hot.

 

I just installed this - not sure how much it will help because I haven't ridden it yet.

 

p_STrearcaliper.jpg

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About once every 5 years. How often do you do it in your car?

You don't ride hard or fast, do you?

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Depends on the bike. Check the lid...or service manual. Most are dot 4. Ok to mix 3 and 4 but not 4 and 5. I havent seen the issueswith a 4/5 mix but i hear its really exciting trying to stop.

Some people never change it, some change it like every week because theyre just so freakin fast.

 

Personally i dont change mine very often. Probably once a millenium. I know, i should change it more.  I hope you guys can accept me as the bad brake maintainer that i am.

 

I did, however, just buy a new mighty vac. But i still didnt change it. 

 

Edit: Manual says xx hours. If i were gonna recommend, id say dark gold, like below.

Edited by jeffdanger
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Do not use DOT 5. It is silicone base and will gum up everything.  Dot ,4 and 5.1 are Glycol Ether/ Borate Ester based and can be interchanged.  Dot 3 is Glycol Ether and should not used with 4 and 5.1.   DOT 5 can only be used if all of the original fluid is removed,this usually involves disassembling master cylinders and calipers to clean them.I was told that even a little ester based fluid in them will cause problems.

 

I use 5.1 because the boiling point is highest . Brake fluid attracts moisture from the air and as it does it's boiling point decreases.  That is why it's important to change it at least once a year to keep it fresh.

 

Remember guys, keep it fresh.

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2X a year is RIDICULOUS! You must be one of those guys who carries a spare piston and rings to change half way through a ride.

 

maybe for you it is.

 

around here in the mountains your brakes will fade much quicker on big descents when the fluid is old, probably has to do with the moisture it absorbs idk.

 

i actually change it when they fade while descending frost mountain. that's my barometer. usually works out to once a year. some folks i know change it at the beginning of mountain season and again at the end. 

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About once every 5 years. How often do you do it in your car?

 

How often do you use the brakes in your car for every ounce of stopping power they have, stop after stop, in rapid succession? My guess would be never.

 

Of course most people also NEVER change their tranny fluid, differential lube, etc. in their cars and trucks. I do.

 

I change the fluid in my bike at least twice a year. I generally change it in my car once a year.

 

Brake fluid is hygroscopic, it sucks water right out of the air. The water creates vapor pockets which reduce braking effectiveness, and causes corrosion issues inside the master cylinder and calipers. I live in a very humid climate, so regular brake fluid replacement is just a good preventative maintenance practice.

Edited by Chokey
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Brake fluid is hygroscopic, it sucks water right out of the air. The water creates vapor pockets which reduce braking effectiveness, and causes corrosion issues inside the master cylinder and calipers. I live in a very humid climate, so regular brake fluid replacement is just a good preventative maintenance practice.

It's a sealed system, how is it gonna suck water out of the air??

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It's a sealed system, how is it gonna suck water out of the air??

The fluid is hygroscopic so it attracts and absorbs water. The brake system may be sealed, but that doesn't mean the materials aren't porous which will allow water molecules to pass through them.

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The fluid is hygroscopic so it attracts and absorbs water. The brake system may be sealed, but that doesn't mean the materials aren't porous which will allow water molecules to pass through them.

LOL! You maintenance police crack me up sometimes.

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LOL! You maintenance police crack me up sometimes.

What, do you think my post was false? Perhaps you should do some reading on how easy it is for brake fluid to hold moisture and how that affects brake performance.

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It's a sealed system, how is it gonna suck water out of the air??

 

 

Some manages to get in through the vent in the master cylinder cap despite the rubber seal, and results in condensation in the air space above the fluid. Water molecules will also penetrate the rubber brake hose through microscopic pores that are too small for fluid to leak out, but large enough for water vapor to pass through.  Water can also get past the seals in wheel cylinders and calipers when they are hot and you drive/ride through water. 

 

It DOES manage to get in there. Brake fluid has a voracious affinity for water, it will hungrily suck in every molecule it is exposed to.

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LOL! You maintenance police crack me up sometimes.

 

 

Why do most automotive manufacturers recommend brake fluid replacement every two years/30,000 miles?

 

Call me "maintenance police" all you want, it's my stuff to maintain as I choose. My insistence on good maintenance is why I have a 12 year old bike that is in nearly showroom condition. It's why I make cars last 10 years or more. My truck is 14 years old and has 150k on it. The truck I traded in on it was 14 years old and had 257k on it. In the long run, my maintenance habits save me money.

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Once a year minimum.

 

LOL! You maintenance police crack me up sometimes.

 

Loose the use of your brakes because of old fluid, and I bet you change your mind, right after you change your shorts or your bandages.

 

I lost rear brakes at the end of a grass track section at a hare scramble and went into the woods way faster than I wanted. It took 2 miles before they came back.After that I didn't use the rears heavy the rest of the race. I had new fluid the next day.

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