2008 GS ONGOING BRAKE PROBLEMS

[Spiderwoman]

I have a 2008 GS with an ongoing brake problem. :dontknow: Had a new tire and pads installed back in June and headed home. Bike threw a code that could not be identified. Back to dealer and Sensor replaced. Headed off to Durango and threw a Parking Brake Failure. Topped off the brake fluid but code continued to flash and brakes were spongy on and off. Took the bike in to a Dealer in Albuquerque who said they thought it was a Master Cylinder. Witout elaborating, we did not have a warm, fuzzy feeling and told the Dealer to put the bike back together and we would get it home. After reassembling the RS, the Code dissappeared. Headed home after Durango with no problems.

Took the bike in for annual maintenance when we returned. The mechanic found the Parking Brake Cable loose and also ground the roter because the brakes had been making an awful noise.
One week later......Another code. BRAKE FAILURE. And again brakes became spongy. Topped off Brake Fluid and code disappeared. Rode about 1000 miles and code appeared again and spongy brakes. Now its again at the Dealer and the discussion is to bleed the brake line. Any ideas on what might be causing the problem. :dontknow:

 

[NancysToy]

The repeated introduction of air into the line does tend to point to a faulty master cylinder, brake caliper, or both...although the leakage could be elsewhere. With this rate of brake fluid loss, there should be visible leakage somewhere. The dealer can perform a brake pressure test, which may show something. I hope you find the answer soon, for your safety. Brake problems never get better as time goes on.

 

[Spiderwoman]

THANKS FOR YOUR INPUT

The repeated introduction of air into the line does tend to point to a faulty master cylinder, brake caliper, or both...although the leakage could be elsewhere. With this rate of brake fluid loss, there should be visible leakage somewhere. The dealer can perform a brake pressure test, which may show something. I hope you find the answer soon, for your safety. Brake problems never get better as time goes on.

Scotty.

The dealer did perform a brake pressure test and he indicated the results were good.
I am hoping this will help narrow down the problem.
Thanks again for your input. Its great to have knowledgeable friends on Spyderlovers.

 

[NancysToy]

Scotty.

The dealer did perform a brake pressure test and he indicated the results were good.
I am hoping this will help narrow down the problem.
Thanks again for your input. Its great to have knowledgeable friends on Spyderlovers.

I wonder if they held the pedal long enugh to see if the pressure held or the pedal dropped (indicating leak by internally within the master cylinder)? Start looking carefully for leaks. Remember, leakage around the calipers seldom shows until it is real bad. It soaks into the brake dust around the pads, and dries up when the brakes get hot. The master cylinder is buried underneath, and won't show much either, especially inside any rubber boot where the shaft enters. A mirror can help you inspect it frequently. Your brake fluid is going somewhere, and air is obviously entering the system. (Air is more likely to enter through the master cylinder end.) If your reservoir has never dropped low enough to allow air to enter, then there is a leak in the closed system somewhere. The trick is going to be finding it before it gets bad enough to cause a catastophic failure. Until then, I'd look at the fluid level before every ride.

 

[Spiderwoman]

Another Question.

I wonder if they held the pedal long enugh to see if the pressure held or the pedal dropped (indicating leak by internally within the master cylinder)? Start looking carefully for leaks. Remember, leakage around the calipers seldom shows until it is real bad. It soaks into the brake dust around the pads, and dries up when the brakes get hot. The master cylinder is buried underneath, and won't show much either, especially inside any rubber boot where the shaft enters. A mirror can help you inspect it frequently. Your brake fluid is going somewhere, and air is obviously entering the system. (Air is more likely to enter through the master cylinder end.) If your reservoir has never dropped low enough to allow air to enter, then there is a leak in the closed system somewhere. The trick is going to be finding it before it gets bad enough to cause a catastophic failure. Until then, I'd look at the fluid level before every ride.

Scotty.

Thanks for the input. Now.. Here is another question for you. Is it possible that the problem I have described could be related to an object lodged in or near the computer on the bike?

 

[NancysToy]

Scotty.

Thanks for the input. Now.. Here is another question for you. Is it possible that the problem I have described could be related to an object lodged in or near the computer on the bike?

Not likely, although you could have a leak at the VCM (Vehicle Control Module) I suppose. This is not a computer glitch, it is a mechanical problem.

 

[Spiderwoman]

Not likely, although you could have a leak at the VCM (Vehicle Control Module) I suppose. This is not a computer glitch, it is a mechanical problem.

Thank you again. Kinda what I thought. Will keep you updated on a final resolution to the problem.