Brake fluid

[Seanie]

Hi,
I changed my front and rear brake fluid today, it looked a bit dark/dirty, and I didnt really know when it was last done by its last owner.

Is there need of bleeding the brakes too do you think? They seem in fine, working order, but after replacing the fluid is it the norm to bleed afterwards and then top it up again?

[hampshirehog]

How did you change the fluid without bleeding the brakes? The norm is to release the bleeders and pump or suck the fresh fluid through until all the old stuff has left the system.

Recommended is to take the calipers to bits and clean them up inside, usually replacing the seals plus inspect the pistons for pitting. Plus fit braided hoses - way better braking as those old original pipes will be swelling up a lot as you pump the brakes.

[SqDancerLynn1]

I usually use a clear hose attached to the bleeder draped into a container with a small amount of fluid in it. Pump fluid thru until it comes out clear

[Nessism]

Suzuki calls for replacing the rubber brake lines every two years, which is obviously excessive, but if you have the original rubber brake lines installed it's fair to say you are negligent in your maintenance. Also, the lines and inside the calipers develop a scale that will not come out with simply flushing the fluid. Listen to hampshirehog and tear down the system and clean it out properly.

[Seanie]

Ouch! "You are negligent in your maintenance" ....Bit harsh Nessism! I only have the bike a few weeks!

I will have goodridge braided hoses fitted by the end of the month, along with new pads front and rear and new tires all going to plan.

I know the hoses are well beyond it at this stage, though the pads are not too bad, but it takes time to get around to these things...

[Nessism]

Ouch! "You are negligent in your maintenance" ....Bit harsh Nessism! I only have the bike a few weeks!

I will have goodridge braided hoses fitted by the end of the month, along with new pads front and rear and new tires all going to plan.

I know the hoses are well beyond it at this stage, though the pads are not too bad, but it takes time to get around to these things...

Tough love! I'm trying to save your life.

[tkent02]

The dark color is due to water in the fluid, and the rust it causes.

Where there is rust, there can be chunks of it. Chunks of rust can block the return port in the master cylinder, can make a brake lock up, even if you don't touch the brake lever. The scale in the lines that Nessism speaks of can do the same thing.
It has happened to a few forum members.

Take it apart, then you will know it's good.

[MAC10]

It has happened to a few forum members.

I am one of those guys. By all means clean the system and replace everything. It is not worth the risk to have brakes locking due to crud in the lines. It can kill you, leave you stranded, or wreck your bike.The feeling one gets when one realizes what has just happened is bad, presuming you stay upright. Take your time and be sure

Look up "Master cylinder cleaning" to find threads about it.