Rear brake locked up

[tbanzer]

Driving bike down road hit rear brake hard enough that abs kicks in, Rear brake does not release. Brake pedal come back to where it should but brakes still locked. no amount of applying front or rear brakes causes rear brake to be disengaged. While completely stopped one press on the rear brake pedal and the rear brake releases. While stopped no matter how hard the brake is depressed it releases. Brake will not remain locked unless rear ABS is activated. Any Ideas?

[maxtog]

Yuck.  You will want to start by supplying more information, starting with what year bike it is, how many miles, and when last was the brake fluid replaced/bled...

[PlaynInPeoria]

Have you ever had the caliper off and cleaned it?

I would suspect the pads won't slide on the pins.  Yank the caliper, pull the pads and clean the caliper well.  I use Windex, it does well, I hose the daylights out of it.  Then run your pins on the wire wheel so they are nice and shiny.  When you put it all back together, put grease on the pins so they slide easily.  Torque them to spec, I also use Loctite.

Try that, if that doesn't fix it, you might need to replace the seals in the caliper.  Either way, I'm guessing you're due for a fluid replacement (not just bled, fluids replaced). Speed Bleeders help immensely with this.

Also, if your fluid is old, it has water in it and heat makes water expand. You use the brakes, heat goes into the system, the water expands, your pads get pushed out and lock up your rear brake.

[tbanzer]

Removed ABS pickup and brakes work like they should without ABS. Reinstall pickup brakes fail to release. When they are locked the pedal is hard with no free travel until I stop , depress the pedal and brake pedal travel is restored. Never flushed brake system, never seen much need since I never  flushed a brake system on any vehicle i have ever owned. Will flush and bleed rear brake and retry.

[MAN OF BLUES]

Yuck.  You will want to start by supplying more information, starting with what year bike it is, how many miles, and when last was the brake fluid replaced/bled...

Agree.....
When you come here and ask a question, and give a breif explanation of a problem, people must give more to go on.... we need to know more specifics on model year, miles, service intervals previosly performed.... etc.... without it, we cannot fully suggest concise instructions to ya..

Now saying the brakes act as normal brakes, when you remove the speed sensor, and the problem reoccurs when it is in place, adds more to the story...
But still not enough info....

We have seen some ABS pump failures this past year, but the symptoms you are saying seem to differ from what those did...

[tbanzer]

2008, 29900mi, oil and filter change and rear gear oil before recommended intervals, original rear brakes still within legal thickness, front rotors and pads changed at about 10,000mi warped rotors. Bike is always stored inside and cleaned regulatory. Original brake fluid still in bike and looked clear in the reservoirs seen no reason to change it, going to flush and bleed brake system.

[Conrad]

2008, 29900mi, oil and filter change and rear gear oil before recommended intervals, original rear brakes still within legal thickness, front rotors and pads changed at about 10,000mi warped rotors. Bike is always stored inside and cleaned regulatory. Original brake fluid still in bike and looked clear in the reservoirs seen no reason to change it, going to flush and bleed brake system.

Water is also clear but if it gets into your hydraulics it can do very bad things. Including screwing up your ABS pump... 

There's a reason that Kawi recommends changing the fluid every two years. 

[maxtog]

Never flushed brake system, never seen much need since I never  flushed a brake system on any vehicle i have ever owned.

2008, 29900mi,

You are way overdue for a brake/clutch fluid change/bleed.  It is impossible to prevent water from getting into brake fluid and like Conrad said,  it can cause bad things.   Is that the cause of your problems?  Unknown.  If there is damage caused by it, will fluid replacement "fix" it?  Unknown.  But it is certainly a cost-effective and sensible first thing to do.  (And I know you said you are going to do it, which is good).

Now I can be yelled at by Conrad because I have not changed mine yet (although mine has 1/3 less miles and 3 years younger than yours).....   but it is on my list.

[Conrad]

You are way overdue for a brake/clutch fluid change/bleed.  It is impossible to prevent water from getting into brake fluid and like Conrad said,  it can cause bad things.   Is that the cause of your problems?  Unknown.  If there is damage caused by it, will fluid replacement "fix" it?  Unknown.  But it is certainly a cost-effective and sensible first thing to do.  (And I know you said you are going to do it, which is good).

Now I can be yelled at by Conrad because I have not changed mine yet (although mine has 1/3 less miles and 3 years younger than yours).....   but it is on my list.

How long is that list of yours Max? Get on it man!

If there are no issues, flushing both the brake and clutch systems can take as little as 20 minutes (depending on the number of beers involved and the distance from the garage to the fridge containing said beers). I used a Motion Pro speed bleeder and the first time I did a flush it went perfectly and I did it in 20 mins. Not so much the second and third times. I allowed air to get into the clutch lines and had a hell of a time getting it out. The brakes went perfectly though.

[PlaynInPeoria]

Speed bleeders are your friend, they make it really easy to bleed the air out.  I have them on both ends and have always installed them on every bike when I replace the fluid the first time.

[deepseamdv]

I made a vacuum bleeder out of an old propane tank, a couple of valves and a vacuum generator all from McMaster Carr. Total cost $35.00 and it works like a charm. I can hook it up to the bleeder and draw a vacuum then just make sure the reservoir stays full until the fluid runs clear and you're done.

[dw4402]

My buddies 2009 was doing a similar thing after he would wash it. Long story short, took his rear brake master cylinder apart and it was all rusty inside of the unit, past the water boot and past the plunger. Cleaned it all up and flushed the fluid and he no longer had the issue. I checked mine (2008) and mine was rusty inside as well, so I disassembled it and cleaned it as well.
Another issue I had was after the dealer performed the rear brake recall my rear brake pedal was way too low. I adjusted it back to where it was before the recall and as I would ride the bike the rear brake would slowly lock up. Apparently the dealer installed the rear brake master cylinder slightly crooked and for some reason this was causing the brake to lock up because once I loosened the master cylinder and put it back straight I haven't had the problem again.
Just some advice that I hope helps.

[NinjaRat]

Curious, can the ABS system be bled like normal brakes or does it require dealer intervention?  My last Triumph had ABS (2006 Sprint ST) and the service manual required using their diagnostic tool to actuate the brakes during bleeding. Incidentally, their diagnostic tool retailed for over $2K, so needless to say I never had to the coin to invest.

[maxtog]

Curious, can the ABS system be bled like normal brakes or does it require dealer intervention?  My last Triumph had ABS (2006 Sprint ST) and the service manual required using their diagnostic tool to actuate the brakes during bleeding. Incidentally, their diagnostic tool retailed for over $2K, so needless to say I never had to the coin to invest.

I have not performed the bleed yet, but from everything posted on this board, the ABS system bleed is no different from a non-ABS.... it will just likely take longer because the system contains a lot more fluid.

[MAN OF BLUES]

Curious, can the ABS system be bled like normal brakes or does it require dealer intervention?  My last Triumph had ABS (2006 Sprint ST) and the service manual required using their diagnostic tool to actuate the brakes during bleeding. Incidentally, their diagnostic tool retailed for over $2K, so needless to say I never had to the coin to invest.

I personally have not serviced gen 2 linked brakes as of yet, but have flushed my gen I ABS system, and there is nothing special to it.
It will require a bit more fluid for the flushing procedure, and a bit more time, but as the system is completely "passive" (I.e. the valves are in freeflow position ) when the bike is off, the fluid pushes thru and all can be bled in a normal manner. There is no "inter mingling" of fluid so to speak from the front to rear, it is just the electrical actuation of the valves that increase the pressure on one end or the other, so the two systems are still seperate and sealed.

[Freddy]

snip< but as the system is completely "passive" (I.e. the valves are in freeflow position ) when the bike is off, the fluid pushes thru and all can be bled in a normal manner. >snip

Hi MOB, how did you determine this?

[MAN OF BLUES]

Hi MOB, how did you determine this?

I have serviced, and disassembled an re assembled my machine.

What was the purpose of your question...? Really.

Have you done the same?
Having asked this, I have fo,lowed your posts about all the complaining on your part, and contactjng nNHTSA and such, and find it a bit of a wasted effort, kf not even futile.

Bantering them doesss nothing, f there is an issues brought to them pristine, and unadulterated, they MAY look, but a one in a thousand thing to them... its just not making them blink..




So explain fully why, and even moreso what, yo have issue with as far as my comment.
Please.

[Freddy]

No issue with your comment MOB, on the operation of the ABS valves, just curious how you came by that knowledge.  I have disassembled & reassembled lots of things on my machines too but not a 1400 ABS unit itself.  Did you do yours?  (Your post does not specify.)  If so, I'd be very pleased to learn more and/or see pix  of the internals of the unit and why some are failing by way of sticking valves, apparently due to lack of maintenance (HD is reported to be having the same problem but with bigger numbers - but that's irrelevant).


I would have looked inside the ABS unit but Kaw wanted my defective 2007-build unit for examination as a condition of them supplying a new one free of charge.

The squeaky wheel gets the oil (sometimes) - as far as reporting goes.   Well, if you own a HD it seems to.   

[Freddy]

Having thought more about what you mean, MOB by "passive" (I.e. the valves are in freeflow position) I think you're simply saying that the is no difficulty with bleeding as the fluid can flow freely through the ABS unit, which as those who have done a brake bleed already know. I falsely thought you were suggesting that the valves were 'floating' when the bike is off - sorry for my not thinking clearly and misinterpreting your valid comment.

NinjaRat's comment about his Triumph is also a valid observation.  The same situation applies to Can-Am Spyders whereby the 'diagnostic tool' is used to cycle the ABS solenoids so that otherwise trapped fluid can be flushed, which is desirable. 

It's interesting that the series 1 Kaw ABS harness has a multi wire plug next to the 2 small fault code wires.  One wonders what it's purpose is.  (The series 2 bike (linked brakes) does not have those 2 diagnostic terminals but will/should display fault codes on the dash when set to do so, but has the multi wire plug.)  Perhaps a KDS-3 connector?  I can find no suggested use for it in the service manual.  Any suggestions?

EDIT:  Yes, the 2 ABS plugs I refer to are for KDS connection.  The series 1 bike has an 8 pin plug while the series 2 has a 6 pin plug.