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Brake fluid

tsconver said:
Yes getting the 2011 today. 9k miles. In great shape, first business to do all the fluids. Then a couple of recalls and then tires. Then ride.

As to your response. No one asked me why I wanted to do it. They said unless you are racing it is not needed. The higher the boiling point of the fluid the better, i don't care how you ride. It will slow the onset of brake fade. I have ran 5.1 in my previous Dot 3/4 bikes with no issues. But none of them were abs equipped. Was hoping someone might have already converted to 5.1 and had experience with it.
Click to expand...

To your original question, I converted my 2003 K1200RS with both ABS and power "whizzy" brakes to Motul DOT 5.1 brake fluid years ago. It is totally compatible with DOT4. I have since converted all my other bikes with hydraulic brakes (and various generations of ABS) to it as well. The advantage I see in all cases is that the Motul 5.1 comes out much cleaner - usually clear like new - when I change it. I live in a dry climate and we just don't get condensation in brake fluid, so only change brake fluid about every three years.
 
GREGFEELER said:
To your original question, I converted my 2003 K1200RS with both ABS and power "whizzy" brakes to Motul DOT 5.1 brake fluid years ago. It is totally compatible with DOT4. I have since converted all my other bikes with hydraulic brakes (and various generations of ABS) to it as well. The advantage I see in all cases is that the Motul 5.1 comes out much cleaner - usually clear like new - when I change it. I live in a dry climate and we just don't get condensation in brake fluid, so only change brake fluid about every three years.
Click to expand...

Curious here, do you test the old fluid with a moisture tester to confirm the 3 year cycle?
What percentage you read?
Clarity is not a reliable indicator of moisture content
 
GSAddict said:
Curious here, do you test the old fluid with a moisture tester to confirm the 3 year cycle?
What percentage you read?
Clarity is not a reliable indicator of moisture content
Click to expand...

Have not used a moisture meter. I came to the two/three year cycles from my own and other's experience with bikes and cars living in this area. Internal brake corrosion is just not a problem. However, never turn down better data, so I'm going to get a meter and start testing my brake fluid. Thanks!
 
GREGFEELER said:
Have not used a moisture meter. I came to the two/three year cycles from my own and other's experience with bikes and cars living in this area. Internal brake corrosion is just not a problem. However, never turn down better data, so I'm going to get a meter and start testing my brake fluid. Thanks!
Click to expand...
They certainly are inexpensive.
I did some experiments with mine when I got it, it does not take much water to get a result.
I always get a chuckle when a client brings in their bike which is overdue for a flush and the tester pins on the scale after they had just said that it looked clear.:eek
Even 1/2 used sealed plastic bottles will start to register after 6 months out here on the Wet Coast.
 
Last edited:
Thanks GSAddict, I'll get one of those on order!

I've always just replaced the brake fluid on an 'as needed' basis. The brake fluid meter should eliminate the guess work.......:wave
 
TheRock58 said:
Thanks GSAddict, I'll get one of those on order!

I've always just replaced the brake fluid on an 'as needed' basis. The brake fluid meter should eliminate the guess work.......:wave
Click to expand...

I have some questions about how this works. I assume you use the tester in the master cylinder reservoir? Is that going to accurately report the moisture content of the fluid in the calipers, or is the master cylinder cover gasket actually the entry point of moisture into a brake system? Secondly, I found some brake fluid test strips which measure for copper contamination in brake fluid instead of moisture. The justification is that copper levels rise when the corrosion inhibitors in brake fluid are exhausted. Is that a good proxy for moisture content? :dunno
 
GREGFEELER said:
I have some questions about how this works. I assume you use the tester in the master cylinder reservoir? Is that going to accurately report the moisture content of the fluid in the calipers, or is the master cylinder cover gasket actually the entry point of moisture into a brake system? Secondly, I found some brake fluid test strips which measure for copper contamination in brake fluid instead of moisture. The justification is that copper levels rise when the corrosion inhibitors in brake fluid are exhausted. Is that a good proxy for moisture content? :dunno
Click to expand...

Replying to my own post - but I found this interesting link about brake fluid myths. One says that modern brake systems don't have a problem with moisture contamination. https://blog.firestonecompleteautocare.com/brakes/everything-you-need-to-know-about-brake-fluid/
 
GREGFEELER said:
I have some questions about how this works. I assume you use the tester in the master cylinder reservoir? Is that going to accurately report the moisture content of the fluid in the calipers, or is the master cylinder cover gasket actually the entry point of moisture into a brake system? Secondly, I found some brake fluid test strips which measure for copper contamination in brake fluid instead of moisture. The justification is that copper levels rise when the corrosion inhibitors in brake fluid are exhausted. Is that a good proxy for moisture content? :dunno
Click to expand...

Any reading of moisture and I flush.
It's so easy, why not?
 
GSAddict said:
Any reading of moisture and I flush.
It's so easy, why not?
Click to expand...

Unfortunately, not all bikes are easy to flush, even with speed bleeders. My K1200RS with the whizzy brakes is a nightmare. I also have five bikes to maintain, so any services which can be set up for a longer cycle are a big help. Plus, I just like to understand what the underlying principles of operation are which affect a system. I'm going to get both the copper test strips and a moisture meter (both are cheap) and test the bikes and cars. Maybe I'll learn something. :)
 
GREGFEELER said:
Unfortunately, not all bikes are easy to flush, even with speed bleeders. My K1200RS with the whizzy brakes is a nightmare. I also have five bikes to maintain, so any services which can be set up for a longer cycle are a big help. Plus, I just like to understand what the underlying principles of operation are which affect a system. I'm going to get both the copper test strips and a moisture meter (both are cheap) and test the bikes and cars. Maybe I'll learn something. :)
Click to expand...

Ride them all weekly, replace brake fluid every two years.

I have some toy cars and currently four motorcycles and have for many years. There is no substitute for working the machines. Solves lots of issues with moisture in metal cases and batteries and rotors and tires and you! If it's not working its rotting.
 
chrisinsc said:
Ride them all weekly, replace brake fluid every two years.

I have some toy cars and currently four motorcycles and have for many years. There is no substitute for working the machines. Solves lots of issues with moisture in metal cases and batteries and rotors and tires and you! If it's not working its rotting.
Click to expand...

I agree with regular exercise, and I would love to do that, but unfortunately, a weekly rotation through my motor pool isn't practical for me. I've started to question a lot of "truths" about vehicle maintenances, like oil changes. I started sending in used oil samples for analysis years ago and found I didn't have to be changing oil nearly as often as is an accepted truth. Has saved money and time, and given peace of mind that I wasn't being a bad car/bike "dad". :laugh
 
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