How often do you change your clutch and brake fluids?

[dirtbird]

Also it's better to use dot 5.1 instead of 4.

I used to think that the main advantage was the increased boiling point but it's not exactly or not only that. 

Recently I had a better look on the TDS of the dot 4 and 5.1 of the brand I work with (N/A in US). Although the boiling point is higher is not by much and there was another specification that caught my attention. 

It's the Wet Boiling Point and this corresponds on how much the fluid absorbs moisture on a given period. 

The difference was much greater (around 40 deg C instead of 10-20), so this means that the 5.1 lasts longer. 

Edited December 19, 2018 by dirtbird

[arc2arc]

If you have a glass port on the side of the brake fluid reservoir look for a darkening of the fluid as an indication that the fluid has begun to absorb water. If you have gone turtle in a ditch or creek its good to be diligent and check for water absorption.  If you let the water-bearing fluid sit in the system it will start to corrode the machined components and cause you all kinds of grief down the road.  In addition, the water can boil under hard braking and the bubbles will make your brakes feel soft. In extreme cases boiling fluid can create leaks in your system as the fluid has nowhere to go. Leaks in a previously dry joint is a telltale sign.  I try and change the fluid in my system every year, regardless of the color, but sometimes it might be 2 years between changes.  If I see the fluid turning dark I change it regardless of when the last change was. 

[MartyMOOSE]

Dot 4 and normally once a month and every of change. It goes off and gets dirty quick.

[weantright]

12 hours ago, savy said:

change brake and clutch fluids once a year ( middle of winter , I live in snow country ) also check  and lube all rear linkage bearings and bushings , wheel bearings, steering head bearings , brake caliper slide pins . all lever pivots, cables , everything that slides-rotates-pivots. engine oil and air filters as needed . when I change a tire I squirt some wd-40 on the spoke nipple ends and give  em a turn , no seized spokes. i ride a lot . and in a lot of wet. my bikes always run and feel new . never break down during riding season.

All this and not a mention of dielectric anywhere.

7 hours ago, dirtbird said:

Also it's better to use dot 5.1 instead of 4.

I used to think that the main advantage was the increased boiling point but it's not exactly or not only that. 

Recently I had a better look on the TDS of the dot 4 and 5.1 of the brand I work with (N/A in US). Although the boiling point is higher is not by much and there was another specification that caught my attention. 

It's the Wet Boiling Point and this corresponds on how much the fluid absorbs moisture on a given period. 

The difference was much greater (around 40 deg C instead of 10-20), so this means that the 5.1 lasts longer. 

I just did this as my clutch master cylinder needed rebuilt. Motul fluid 4 has a higher wet boiling then 5.1 and 5.1 has a higher boiling point then 4. Both boiling points were not widely different and I choose 4 for the wet boiling point. Really doesn't make a difference IF you change at least once a year.

[lotus54]

I also use a bit of Girling brake rubber grease on the screws for the cap. That keeps them from corroding and causing issues.

it is designed to work with brake fluid, I’ve been using it for decades.

Mark

[savy]

grew up on two strokes , compression release era, and drum brakes, they sucked. moved on to modern four strokes , with disc brakes , great brakes and engine compression slowing down power. don't have to use brakes that heavily. back to riding modern two strokes , great bikes , but with little compression braking power , had to learn all over how to use brakes more heavily . which means a little more servicing of fluids. ride with a couple guys who did little service to there bikes, and watch them loose brakes on steep downhills ( 2 strokes) dirty brake fluid , and blue rotors. laughed at em ,and suggested to do a little maintenance , they do now. and son of a gun , there brakes are back. 

[RacingDVD]

18 hours ago, weantright said:

All this and not a mention of dielectric anywhere.

 

How does that work? Do you use dielectric grease for all the connectors? Open them up and use the grease inside them?

[weantright]

4 hours ago, ocdaan said:

How does that work? Do you use dielectric grease for all the connectors? Open them up and use the grease inside them?

Yes, then make sure the connectors lock/stay together. Tape if needed.  Beta’s are among the worst with quality of connectors. 

[savy]

the dielectric grease on all connectors was done first thing when bike was new. pretty much once is enough, unless connector is opened.

[little_wing]

for changing out the clutch fluid, can I use a vacuum pump on the bleeder screw?? then just keep re filling the master until I get clean fluid out the bleeder??  

[savy]

sure , I've used a syringe and sucked the fluid out , just like you mention. you can also push new fluid in. pushing fluid up is a great way to get air out of the system if needs be.

[Weezer the Geezer]

 The idea of changing brake and clutch fluid frequently  is a relatively new idea developed to get $ out of your pocket.  I was a GM certified auto technician in the 1960s and 70s and we never heard of doing so.  LOL, Probably because if your system got water in it, and pitted your cast iron master cylinder, or brake cylinder, we got to replace it for you. 

But since they went to disc brakes and stopped using cast iron wheel and master cylinders on the old cars, and developed better brake fluid, I have never changed fluid, and never had a problem.  Some of the cars we have driven for 10 or 12 years. One Nissan had over 200,000 miles on it, had the pads changed several times, but never had a caliper problem, or fluid changed.

Only in the last few years have I had bikes with disc brakes. The only one I flushed and changed the fluid on was one that had been submerged in water and got water in the system.  

If you feel good about changing your fluid....go for it!  It's your $ and time.  But my experience tells me it only needs to be done if it gets water or trash in the system.  Or if you need to change your caliper or master cylinder, go ahead and flush it.

[lotus54]

It is certainly not a new idea at all.  Manual from a few of my 1960’s cars said to do so every two years at the most.

  It is a lot more than the corrosion- if any amount of moisture it abosorbed, the brakes will fade rather spectacularly if good and hot. I’ve seen it.  Now= if you live/ride in a very dry climate, it may not be an issue.  But I ride in the rain all the time, and it is an issue if you don’t flush it.  It is easy, cheap and I can so no reason not to do it myself.

 

but just my experience. 

[weantright]

The hotter you get your brakes the more you feel a need to change fluid.

[Weezer the Geezer]

3 hours ago, weantright said:

The hotter you get your brakes the more you feel a need to change fluid.

Good point.  I hadn't thought about the heat factor.  I'm a woods rider and never get my brakes really hot.

[El Diablo Rojo]

I do both the brake(s) and clutch fluids every spring in all my bikes. Reverse bleed FTW[emoji16]

[Marco the Pool Boy]

I’m a woods rider and I use my brakes a lot, so I change my brake fluids yearly as they get hot and its evidenced by contamination in my brake fluids. Also the hydraulic clutch assembly on my Beta, shows the same contamination. But I do have the Rekluse 3.0 Core clutch assembly so that may increase a little extra heat within the engine.
I performed bleeding/flushing of my brakes and clutch 2 weekends ago with a vacuum bleeder, it took less than an hour and costed maybe $5.00 in fresh fluids. I always use a fresh sealed/unopened small container and toss the remaining fresh fluids to negate moisture entering the container on the shelf....

[El Diablo Rojo]

I’m a woods rider and I use my brakes a lot, so I change my brake fluids yearly as they get hot and its evidenced by contamination in my brake fluids. Also the hydraulic clutch assembly on my Beta, shows the same contamination. But I do have the Rekluse 3.0 Core clutch assembly so that may increase a little extra heat within the engine.
I performed bleeding/flushing of my brakes and clutch 2 weekends ago with a vacuum bleeder, it took less than an hour and costed maybe $5.00 in fresh fluids. I always use a fresh sealed/unopened small container and toss the remaining fresh fluids to negate moisture entering the container on the shelf....

Try reverse bleeding next time. It's way more efficient than a vacuum bleeder.

[Ocaptainmycaptain]

1 hour ago, VELORACERMIKE said:

1 hour ago, Mark-us-B said:

I’m a woods rider and I use my brakes a lot, so I change my brake fluids yearly as they get hot and its evidenced by contamination in my brake fluids. Also the hydraulic clutch assembly on my Beta, shows the same contamination. But I do have the Rekluse 3.0 Core clutch assembly so that may increase a little extra heat within the engine.
I performed bleeding/flushing of my brakes and clutch 2 weekends ago with a vacuum bleeder, it took less than an hour and costed maybe $5.00 in fresh fluids. I always use a fresh sealed/unopened small container and toss the remaining fresh fluids to negate moisture entering the container on the shelf....

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Try reverse bleeding next time. It's way more efficient than a vacuum bleeder.

How do you reverse bleed?   I've never changed out clutch or brake fluids myself on any bike that I've owned, but this is something I'd like to learn how to do, so I don't have to rely on a mechanic.

[El Diablo Rojo]

How do you reverse bleed?   I've never changed out clutch or brake fluids myself on any bike that I've owned, but this is something I'd like to learn how to do, so I don't have to rely on a mechanic.

This vid is for an Aprilia Tuono but the concepts will work on any car or bike. The advantage to reverse bleeding is it forces the air up and out (it's natural path). I've been doing it this way for years and it's way better than any other method I've tried.