Hey everyone,

I'm having a problem, and wondering if any of you have ever encountered this.

My '95 1000F's front brakes have become real touchy-grabby. The lever comes in a bit, then sticks, then will suddenly come in some more. It's tough to get consistent pressure on the front brake. It doesn't matter if the bike's moving or not. Do I need to rebuild the master cylinder, or what's the deal?It makes stopping pretty risky, so I've been using my other bike for the last few weeks.

Any thoughts?

Thanks, in advance, for any words of wisdom.

 

I would start to remove the calipers, give them and the pistons a good clean and put in new pads. If the problems remain, itwould betime to check the main cylinder.

 

I changed the padsand checked out the calipers (I should have mentioned that in my post). The calipers looked and felt fine.

Something else I should have mentioned: I have the linked braking, and the rear pedal doesn't have any of the grabby-sticky thing.

 

When you look in the little window on the side of the front break master cylinder, what color is it ? If it's brown or dark in color, then your brake fluid is contaminated.Brake fluid absorbs moisture over time and it turns brown (not sure if that's why it changes color). Old brake fluid doesn't have the same viscosity properties as new fluid and doesn't move as freely. Buy a rebuild kit for the master cylinder and flush with new fluid at the same time. That should bring your nice smooth lever action back. It worked wonders on my 1KF and my wifes F3. I currently have the same issue with a 98 F3 I just bought. I'll be rebuilding it soon.

 

The linked breaks have nothing to do with your problem.

When the lever is squeezed, fluid goes to the outer pistons in the front calipers and nowhere else. Due to the fact that you say that the problem is present when the bike is not moving tells a story. When the bike is moving the wheel is spinning and the break pads will push the pistons in some. When the bike is stopped this will not happen and the pistons will be pushed out and stay there.

The only place the problem could be coming from is the master cylinder.

If your bike had been sitting with some water in the reservoir, it may have rusted and is now causing the sticking.

 

Well, I decided not to wait until I had the rebuild kits for the master cylinder and callipers before flushing with new brake fluid. Boyam I glad of that. Man what a difference it made. Flushing the fluid was such an easy job to do. I just took the lid off of the master cylinder, put a hose on the bleeder fittingfor the calliper to run the old fluid into a bucket. I pumped the lever a few times, then held in place while cracking the bleeder open a bit. When the lever hit the handle bar, I held it there while closing the bleeder. Then pumped a few more times and then repeated. I kept pumping until the master cylinder was almost empty of the brown fluid, making sure not to expose the drain in the bottom so air bubbles wouldn't get into the lines. I topped off the reservoir with fresh and kept pumping and bleeding until clean fresh fluid came out the bleeder on the calliper. I switched to the other front calliper and repeated the procedure until it bled clear as well. That smooth feeling came back to thefront brake lever, and it now has predictable braking in the front. Itturned out so well, that I did the rear as well. I've got some photos showing the dirty fluid and how thingswent.

[IMG]local://upfiles/10297/5AB09E602FFA4A75AF20726935490F57.jpg[/IMG]

[IMG]local://upfiles/10297/0D811BCCFC804CC78E957444E934A1FC.jpg[/IMG]

[IMG]local://upfiles/10297/769BF8A9C6D54FFCBB6421F30AFCC27C.jpg[/IMG]

[IMG]local://upfiles/10297/CDC1F345CF1F49D799F567D074406FF2.jpg[/IMG]

[IMG]local://upfiles/10297/0E9D0D7500404803ADD2DDBAB15C843C.jpg[/IMG]

 

Some additional photos.


[IMG]local://upfiles/10297/3CACFAC0B0474B8EA6D1C4FA27999CC0.jpg[/IMG]

[IMG]local://upfiles/10297/2DAC21DBB4E84FCB8A15D1E5172E58D3.jpg[/IMG]

[IMG]local://upfiles/10297/C0EB1D32677149DAB96E575FE5EAC262.jpg[/IMG]

[IMG]local://upfiles/10297/9F3146FE77684EDBAF458CF1BE3F2378.jpg[/IMG]

 

wow, that fluid was deffinetly bad. Pretty amazing what new fluid will do =)