Front brakes dragging......again!

[stlheadake]

Ok folks, I've posted previously about this, and it is happening again.  My front brakes are dragging.  At some point I used them and now they don't release.  I can hear them rubbing at highway speeds.  I grab a hand full, and then release a couple of times, but nothing.  They continue to drag.  By dragging I am saying that when I get home, I put the bike on the center stand and give the front wheel a spin.  It won't turn more than about 1/8 of a turn on it's own.  I am convinced that this is how my first set of rotors warped.  I've had them (both) replaced and all has been well until now.

The last time they did this, I took them apart as soon as I got home (this is about 1500 miles ago) from my ride.  I cleaned them with brake cleaner and a tooth brush.  I cleaned all around the pistons and pucks, scrubbed all the mounting gear and keepers.  After all that, put it back together, and it all started again a thousand miles later.

To be honest, I don't 'regularly' clean them unless I have a problem like this.  I find it unacceptable to 'HAVE' to clean my brake calipers so regularly.  What gives?   Anyone else noticing any thing like this?

edit: I never did find a 'cause' of the failure to release.  I just cleaned them all up, and reassembled them, and they worked.

[redbarber]

I'm no expert, but I suspect that something is amiss with your master cylinder.  When you release the brake, the fluid you pushed down into the pistons needs to be allowed to return to the reservois.   Can you tell if both calipers are dragging?  (Maybe check for any free play in the brake pads, if only one is dragging, maybe the other one will have a tiny bit of wiggle room.  In any case, this is a flaw, because I'm positive if there was anyone else having this problem, you'd have heard about it long and loud on this form.  Mary Jane would never put up with this type of issue.

I'd get it to the mechanic and demand they resolve this before it causes an accident.

[stlheadake]

It IS both calipers.  They are only dragging enough for me to hear them, I don't FEEL it.  I normally ride with ear plugs in and yesterday I didn't, so I heard them.  As soon as I could get it up on the center stand, I could feel the drag in the wheel.  I'm going to call and see if it is something I can get covered under warranty.  I will more likely just flush/bleed them and see if I can find anything.  It's just confusing that when I cleaned the calipers it started working fine.

I USED to clean my bike regularly, and couldn't help but to blast my calipers to blow out the dust.  I wonder if that was what was keeping them 'clean' and working properly?  I whole-hardheartedly believe this IS related to  the cause of the rotor warpage issue!  My rotors were fine until the brakes started dragging.  Toss in a couple rides in the rain, then BAM!  Of course this is only anecdotal, I have no research, but I'll bet they are connected!

[jjsC6]

Could you tell us more about what has been done in the past.  Have they been worked on, and are you running stock pads?  Do you get a lot of brake dust on your wheels?

[kawacop1642]

I had a similar problem with mine. However, it was only when I used the link break system. I would start to smell breaks burning and thought it was the car in front of me until, out of curiosity, I pulled over and checked my brakes, and noticed the front disc was slightly discolored and extremely hot. Once I disengaged the link system, it was fine. I still have to bring it to the dealer to get it checked.

[Steve Bell]

My stock Kawasaki brake lever was preloading the piston in the master cylinder too much causing my brakes to drag, drilled the small hole in the lever that the piston sits in a little deeper and no more drag at all. I'm sure this is why the rotors warp. I posted this in one of my warped rotor threads as well.

[stlheadake]

Could you tell us more about what has been done in the past.  Have they been worked on, and are you running stock pads?  Do you get a lot of brake dust on your wheels?

It was worked on about 1500 miles ago when the dealer replaced the rotors because the previous set were warped.  This has happened off and on for some time now.  I have about 5K on a set of EBC pads.  In the past, I have pulled the calipers, removed the pads, and judiciously cleaned the calipers with brake Kleen and a tooth brush.  Blast it all out with air, and reassemble.  This has worked.  Last night I pulled the calipers, and worked the brakes, collapsing the pads and opening them up.  They close evenly on both sides.  Aside from being 'dirty' they seem to work just fine.  It was late, and I wasn't in the mood to go any deeper, so I reassembled them.  And guess what?  They still drag... bummer!

Tonight, I am going to take them apart again and clean them and see if there is something 'binding' or causing them not to release.  I suspect dirt in the lines, piston or in the Master Cylinder myself.   Something is holding them closed.

I had a similar problem with mine. However, it was only when I used the link break system. I would start to smell breaks burning and thought it was the car in front of me until, out of curiosity, I pulled over and checked my brakes, and noticed the front disc was slightly discolored and extremely hot. Once I disengaged the link system, it was fine. I still have to bring it to the dealer to get it checked.

I have an 08, that was before the failed attempt at making everyone a safer braker with linked brakes!  So that isn't the problem.  I'll flush and bleed them out this weekend and see if I get any grit out.  It's just frustrating!  I can't afford to park the bike, because that forces me to drive the beast.  When I drive the beast, I have to spend all my food money on fuel.  The beast is my 4x4 diesel RV/work pulling rig.

[B.D.F.]

Just a suggestion but before you modify the brake lever you might want to make sure there is residual pressure in the system, otherwise you will be 'fixing' a problem you do not have while the real cause goes on.

With no pressure on the brake lever and the brakes dragging, crack the brake bleeder on the master cylinder and see if there is any pressure in the system. A short length of clear vinyl hose will help prevent the fluid from getting onto any paint or plastic on the bike, and let you see the fluid move in the tubing. Put the tubing on the bleeder before time and then just crack the bleeder and watch to see if any brake fluid appears inside the tube. You might want to plug the end of the tubing so it is not possible for any brake fluid to escape- that stuff eats plastic and paint so be careful not to let it 'get away'.

Brian

I must have not hit post!  I wrote a reply this morning, and apparently left it on my desk at home!  The dealer replaced two warped rotors about 1500 miles ago.  I am using aftermarket EBC pads that have about 3K on them.  They are in great shape (FOR NOW!), but I fear they won't be.  This problem seems to come and go.  If I give the calipers a clean up, it seems to go away. 

Steve I remember reading your posts about your modifications.  However I don't REMEMBER reading your post.  How involved is drilling out for the piston?  If I am seeing this correctly you just re-located the hole for the piston pivot?

[stlheadake]

Steve did you just re-locate the point that the piston attaches?  I have not looked at the mechanics of the lever yet, but is it obvious to see it applying pressure?  Does drilling change in any way the 'feel' of the brake(s) or lever?  Do you happen to have pics?

Your info is appreciated. 

[stlheadake]

Thanks Brian!  I will try that tonight.  I was figuring on flushing the system this weekend.  So let's just say that there is residual pressure in there.  When I crack the bleeder, I get some fluid out.  Where would that pressure have come from in a closed system? 

Just a suggestion but before you modify the brake lever you might want to make sure there is residual pressure in the system, otherwise you will be 'fixing' a problem you do not have while the real cause goes on.

With no pressure on the brake lever and the brakes dragging, crack the brake bleeder on the master cylinder and see if there is any pressure in the system. A short length of clear vinyl hose will help prevent the fluid from getting onto any paint or plastic on the bike, and let you see the fluid move in the tubing. Put the tubing on the bleeder before time and then just crack the bleeder and watch to see if any brake fluid appears inside the tube. You might want to plug the end of the tubing so it is not possible for any brake fluid to escape- that stuff eats plastic and paint so be careful not to let it 'get away'.

Brian

[B.D.F.]

The master cylinder. Either a clogged port in the master cylinder or the master cylinder piston is being held in slightly, again causing a clogged port (clogged with the MC piston seal in this case).

When a vehicle brake system is released, the spring(s) in the system push the master cylinder piston back far enough to uncover the reservoir feed into the master cylinder. This makes it impossible to pressurize the system, even if the cause of that pressure is coming from somewhere else like the fluid in the system expanding due to caliper heat or anything similar. In fact, you cannot pressurize the system even if you tried- for example, pushing the caliper piston(s) back will not pressurize the system, they simply move brake fluid from the caliper back into the reservoir. So anytime there is residual pressure in the system, the master cylinder to reservoir post must be blocked in some way, either by debris or the master cylinder piston not fully retracting (as Steve has mentioned).

As an aside, it is usually one or more pistons dragging in the caliper that causes dragging brakes in a [non sliding] caliper brake system like the C-14 has. It might be a ridge of crud or corrosion on the piston, and it only has to be one of them. It could also be a hydraulic system flaw where there is debris preventing the release of pressure from the caliper but that would be very unusual because those ports are very large compared with the master cylinder to reservoir port.

Brian

Thanks Brian!  I will try that tonight.  I was figuring on flushing the system this weekend.  So let's just say that there is residual pressure in there.  When I crack the bleeder, I get some fluid out.  Where would that pressure have come from in a closed system?

[Steve Bell]

Steve did you just re-locate the point that the piston attaches?  I have not looked at the mechanics of the lever yet, but is it obvious to see it applying pressure?  Does drilling change in any way the 'feel' of the brake(s) or lever?  Do you happen to have pics?

Your info is appreciated.

When you take the lever off and then try to re attach the lever again you will notice in order to get the bolt back into the lever the piston in the master cylinder  will need to be depressed slightly, in my mind this is not normal because as the piston is depressed the pads will start to move. I drilled the small hole in the lever that the piston sits in slightly deeper to allow the mounting bolt to drop into the lever without any extra pressure on the piston. No more brake drag and the lever still feels the same. The hole only needs to be slightly deeper maybe 1/16" or so. Sorry I have no pictures.

[stlheadake]

Well last night I tried Brian's suggestion of cracking the bleeders to see if there was pressure.  Guess what?  There was a little.  I cracked both and though I didn't get the 'rush' of oil I anticipated, there was some.  Since I had my bleeder kit connected, I went ahead and bled both sides.  I actually flushed a fair amount of oil through both calipers.  I didn't see any dirt or anything peculiar.

The brakes did release some, and now only slightly drag.  A modest spin of the front wheel yields maybe 3/4 to a full rotation.  I think it should be even more free, but I don't have anything to compare it to.  But the biggest change is in the lever!  At the lever it used to feel very tight, as in there was no lever action.  It felt 'pumped up' all the time.  Now they feel more 'normal' in that there is a lever 'action', you have to squeeze and you feel the lever applying pressure to the brakes.

I do not declare victory, as I still feel like there is something binding, but I feel better that I am at least close to the issue.  Maybe I have the same problem Steve was having with his, I don't know, but I should think that if it happens again, I will pull the lever to see if that releases the pressure.  If it does, then I will KNOW what my next step is. 

[VirginiaJim]

Make sure you don't have the reservoir overfilled.  Don't ask me how i know about that one....

[stlheadake]

Make sure you don't have the reservoir overfilled.  Don't ask me how i know about that one....

OOOOHHH!!! I uh won't ask, but what happens?  I mean not implying that YOU would know first hand or anything.  It was right at the top of max, then I put the cover on.  I don't think it's over filled.  But the light in the garage was not good for sure.  JEEEEEZ, now I have to feign a bathroom break and check!

[VirginiaJim]

OOOOHHH!!! I uh won't ask, but what happens?  I mean not implying that YOU would know first hand or anything.  It was right at the top of max, then I put the cover on.  I don't think it's over filled.  But the light in the garage was not good for sure.  JEEEEEZ, now I have to feign a bathroom break and check!

What happens, he says....nothing good I say.  Too much fluid, the calipers won't/can't retract, hence the rotors overheat, hence the pads lay down material in all the wrong places, hence shuddering rotors, I can go on and on....  Just make sure you only have it to the line in the reservoir with the reservoir level.

[stlheadake]

What happens, he says....nothing good I say.  Too much fluid, the calipers won't/can't retract, hence the rotors overheat, hence the pads lay down material in all the wrong places, hence shuddering rotors, I can go on and on....  Just make sure you only have it to the line in the reservoir with the reservoir level.

  That's all?  I'm Safe!  Jim you had me  scared!  I am at the top, but it's safe.  On the same but different topic , how hard is it to bleed the clutch?  While doing all this, I noticed how dark my clutch fluid is. 

Honestly I haven't even looked at the clutch mechanism beyond the master cylinder and or the oil fill.  The bleeder is probably sitting right there, and I've never pain any attention!  I came from BMW with a dry clutch, and hours of pain and many specialized tools involved in such matters!

[Conrad]

  That's all?  I'm Safe!  Jim you had me  scared!  I am at the top, but it's safe.  On the same but different topic , how hard is it to bleed the clutch?  While doing all this, I noticed how dark my clutch fluid is. 

Honestly I haven't even looked at the clutch mechanism beyond the master cylinder and or the oil fill.  The bleeder is probably sitting right there, and I've never pain any attention!  I came from BMW with a dry clutch, and hours of pain and many specialized tools involved in such matters!

The clutch is even easier than the brakes. The only bleeder that you really need to worry about is the one down low on the left side, in front of the shifter. Just hook up your bleeder kit and away you go. 10 min job.

[stlheadake]

The clutch is even easier than the brakes. The only bleeder that you really need to worry about is the one down low on the left side, in front of the shifter. Just hook up your bleeder kit and away you go. 10 min job.

Awesome!  I was hoping for that!  The fluid looks pretty dirty in the reservoir, so I might as well clean it up.

[Tactical_Mik]

The clutch is even easier than the brakes. The only bleeder that you really need to worry about is the one down low on the left side, in front of the shifter. Just hook up your bleeder kit and away you go. 10 min job.

vacuum out the res. first without taking too much out and allowing air to enter.  Fill res. and move to slave and bleed.  No point in dragging all that rubber and such through the whole system.