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Discussion Starter #1
The front break on my 94 Vulcan has started to feel spongy when I apply firm break pressure. It gives and gives a little more but there still seems to be plenty of travel, but my breaks don't feel quite as strong as they should be especially for dual rotors.

A mechanic friend of mine thinks it's water in the break line and that some rubber components in the master cylinder and the calipers are probably rotted and need replaced. Is the problem that serious or will a simple break fluid change solve it?
 

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The Professor
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The front break on my 94 Vulcan has started to feel spongy when I apply firm break pressure. It gives and gives a little more but there still seems to be plenty of travel, but my breaks don't feel quite as strong as they should be especially for dual rotors.

A mechanic friend of mine thinks it's water in the break line and that some rubber components in the master cylinder and the calipers are probably rotted and need replaced. Is the problem that serious or will a simple break fluid change solve it?
Drain the system, repace the Master Cylinder seals and use Valvoline DOT4 Synthetic Brake Fluid. :smiley_th
 

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Search Goddess
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Is your brake fluid a nice amber color or does it look more like muddy water?
Old brake fluid will produce spongy brakes. Simple enough to check if you just look at the sight glass on the front of your Master Cylinder.
Brake fluid should be changed every year or so since it does tend to pick up moisture even with good seals.
 

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Discussion Starter #4
The fluid color is a darker amber/brown and no sign of muddyness at all.

Lance, what master cylinder seals exactly are you referring to? All of them? lol
 

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The Professor
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The fluid color is a darker amber/brown and no sign of muddyness at all.

Lance, what master cylinder seals exactly are you referring to? All of them? lol
You have to buy the complete piston assembly, seals are not sold seperatly.
 

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Undercover Sportbiker
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Start with the brake fluid replacement. If that doesn't work, I can probably set you up with a working front m/c dirt cheap.
 

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A mechanic friend of mine thinks it's water in the break line
Regular brake fluid is glycol based and hygroscopic, meaning it absorbs moisture. Humidity and weather conditions in your area determine how much and how fast and contributes to the color change from clear amber to muddy brown. Brakes fluid needs to be change about every 2 years on average (on all vechicles).

I do this on all my vehicles and it is like having brand new firm brakes.
 

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Discussion Starter #8
Ok guys! After a brake fluid change my brakes feel much much more solid. The fluid was way past its prime. I had no idea new brake fluid was clear haha!

Thanks for the help!:beerchug:
 

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My Fluid looks like think chunky muddy water. I want to drain the system and completely remove it but the two screws are seized. I have been soaking them in PB plaster for a few weeks, i think i have to remove the resevoir from my bars and use an impact wrench because they screws are pretty mangled. Could I just use dot 3 since i have a whole bottle?
 

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I totally dissassembled my breaks. lines of, everything. The fluid was brown and was contaminated with water. I did get the screws out with the impact wrench, works great! i took the piston out of the resevoir, and you would not believe how much junk was in there. Tomorrow i will flush everything out, bench bleed it, then hook it all back up.
 
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