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  #1  
Old 10-23-2007, 11:36 AM
JW-Spud JW-Spud is offline
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Pics of ABS II Internals

Here are photos of the internals of the ABS II pump.

#13 is the bleed ports/ cyl cap
#15 - pistons
#16 - clutch assy
#17 - Clutch
#20 - computer attachment that shows the antenna wires
#21 - computer
I will also have to revise my impression of the chain. It goes from the shaft lobe through a roller on the bottom of the piston to the sidr of the case. It gives the mechanical advantage of two to on and a very short stroke of approx 3/32.
The piston is nylon with a metal core. It also looks like the seat for a check valve is in the top of the piston.
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  #2  
Old 10-23-2007, 07:33 PM
voxmagna voxmagna is offline
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Re: Pics of ABS II Internals

Hey Spud, those antenna wires? From your photo they look like 4 pairs coming from/going to an 8 pin socket.

If there are 2 separate pistons, don't you think each wire pair is a limit sensor for each end of the piston travel which would make sense. Is there a socket/plug picking up on those 8 pins?

Can you push the pistons in any shape or form? If the pistons are at one end have you got 2 pairs of those wires showing low ohms/short circuit? If you can push the pistons to their opposite end, do the other 2 pairs go low ohm?
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  #3  
Old 10-24-2007, 11:11 AM
JW-Spud JW-Spud is offline
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Re: Pics of ABS II Internals

Voxmagna, the antenna wire is looped around the clutch assembly. It goes from the plug around the outer edge of the clutch and right back to the plug without any apparent connection. The plug with the two antenna loops is the only electrical connection from the mechanical drive to the computer. You may be able to see an eight pin connector on the computer circuit board. Thats it. no other sensors or switches are seen and there are no other wires inside the clutch unit.

It is possible to move the pistons by hand. In order to do it you must use a lever to move the spring loaded clutch assembly in order to rotate the shaft. when I first tried this I felt no movement of the piston. When I pressed harder with my finger I felt the piston move at most 3/32". It seems that the piston only moves when there is both brake line pressure (simulated by finger method) and the movement of the clutch cam chain. So once again it would seem that without access to the lower mechanicals there isn't a way to exercise all of the circuit. If you were to just open the top of the ABS bleed port/ piston with a 22 mm thin wall socket. It wouldn't be possible to move the piston without alot of force. Its just with the combination of manipulation of the clutch and pushing down on the piston at the same time that will determine the mobility of the piston. There is also a check valve in the center of the piston that may play a part in the metering and regulation of line pressure. A piston in a valve inside a piston.....great! I couldn't feel any movement of the inner valve piston but I may try it again before I seal the unit up again. If you were willing to remove all of the bearing supports from the main shaft and lift it away from the case it may be possible to remove the pistons. However, and this is a big however, if there are seals or rings on the piston there would be one hell of a fight getting it back in.

Voxmagna, I understand the question about the wires and possible piston limit switches and I can assure you that there are no limit switches or connections seen.

The best comparison I can offer is of an air conditioning clutch that when activated closes. The big difference here is that the clutch assembly gets energized by a momentary high frequency antenna signal from the ABS computer instead of a direct connection. It is possible to send energy via high frequency safely for short distances. You better be well grounded

Jeff
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  #4  
Old 10-24-2007, 04:52 PM
voxmagna voxmagna is offline
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Re: Pics of ABS II Internals

I'm amazed that for this dynosaur generation of bike electronics, they should think of anything controlling your brakes that uses radio.

Oh I thought you had all the bearings and cross tube out? I had all mine out with the ABS module out of the battery tray and sitting on the shelf. I had this idea it would give me more room when I took the swingarm and motor out of the frame. It wasn't too hard coupling everything back up. We do have the friendly ABSII bleeding wise!

You've actually moved some pistons, so at least you know they aren't seized.

Thanks for more write up.
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  #5  
Old 10-25-2007, 10:44 AM
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Re: Pics of ABS II Internals

I must make a retraction and correction to my earlier posts concerning the antenna theory. It was based upon what I could see from the open base cover. After a closer inspection I am not sure that the wires are just looped around the clutch assy. In order to gain access and expose the opposite side of the clutch it would be required to pull all 4 of the bearing caps. The caps appear to have pressure fit sleeves inside the bolt holes. I didn't want to pry them all up and risk damaging any of the surfaces. I will try to inspect it with a small fiber optic scope that I can borrow. It is starting to look like a direct connection ,which would make more sense. It would still require slip somewhere. But I am done with assumptions on this unit. Plus I want to have this one as a mechanical spare.

Jeff
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  #6  
Old 10-25-2007, 08:54 PM
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Re: Pics of ABS II Internals

great post
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  #7  
Old 10-28-2007, 06:56 PM
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Re: Pics of ABS II Internals

Radio? Cool. So if one of these bikes is sitting next to me in traffic and I key up 1500 watts of HF with my ham radio in my car while yaking with some guy in New Zeland there might be some funny stuff going on in the ABS unit?

Brillant indeed.

Well so far 50 watts of vhf or uhf hasn't affected anything on my bike and I don't intend to run HF so I guess I just better watch out for vehicles with those big screwdriver antennas.
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Old 10-28-2007, 07:12 PM
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Re: Pics of ABS II Internals

Quote:
Originally Posted by BerryG
Radio? Cool. So if one of these bikes is sitting next to me in traffic and I key up 1500 watts of HF with my ham radio in my car while yaking with some guy in New Zeland there might be some funny stuff going on in the ABS unit?

Brillant indeed.

Well so far 50 watts of vhf or uhf hasn't affected anything on my bike and I don't intend to run HF so I guess I just better watch out for vehicles with those big screwdriver antennas.

I think Spud may be reviewing his ideas about radio! Can you get free gas from the pump with VHF?

73's - Vox
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  #9  
Old 10-28-2007, 09:14 PM
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Re: Pics of ABS II Internals

Fee gas? Gawd I wish.... But I don't transmit around gas pumps..
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  #10  
Old 10-28-2007, 11:20 PM
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Re: Pics of ABS II Internals

Jeff,
that is facinating stuff......kudo's to you for opening it up/anaylsing/photographing.

Like yourself, I'm not buying the 'radio antenna' idea either.....question- could the wires to the clutch assy. possibly be part of position/slip circuit (the reverse of the ABS wheels sensors) ?
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  #11  
Old 10-29-2007, 10:28 AM
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Re: Pics of ABS II Internals

The antenna theory is dead. After looking into the narrow gap with a scope it looks like the wires go into the clutch assy. There is just no other way to see into there without disassembly. Sorry for any confusion but it is just an electrically activated clutch with the darn wires hidden.

I forgot the rule about keeping it simple.

An update: I am expecting my ABS relay and base this week. I also have another Hydro unit I found on the way.
After I took apart the relay base I found a diode that was bad. It was split from heat. It was a common rectifier diode. I replaced it and rewired the base of the relay base. I also took apart the relay and cleaned the contacts. All of the wire connections were then coated with heat sink compound and tested for continuity. I am still going to try the original unit without any new parts to see if this thing is salvageable. I will keep you posted.

Jeff
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Old 10-29-2007, 11:28 AM
voxmagna voxmagna is offline
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Re: Pics of ABS II Internals

The diode across the relay coil should be reversed so it does nothing when the coil voltage is the correct polarity. It's there to protect the ABS computer from voltage spikes coming back off the coil. Did you test the diode and was it a short for polarity both ways? This is the most common problem and the easiest to fix. I can't remember your original fault, but a short circuit diode would stop the relay bringing on the pump and the ABS relay driver would not see normal current. I hope the upstream ABS relay driver is still OK. Any old power diode will do, A couple of amps at 1000 volt will be strong. Get it the right way round!!

On the mistery wires you found, can you just note their colors and any resistance readings you see on both pairs?

Whenever I have 2 identical items in front of me with a bundle of colored wires/terminals sprouting to connectors, one working one suspect, I always draw up a table and try to measure every wire resistance to every other wire resistance both ways round (yes it can be a big table!). Even if you can't understand the readings at first, they should be similar across both units. Clearly a very low resistance (short) on one unit and not the other is worth looking into, even if there's a logical reason, like the rest position for the pistons and clutches are different

I did this for my TPS.

Thanks - Vox
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Old 10-30-2007, 10:46 AM
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Re: Pics of ABS II Internals

Vox, before I sealed up the unit last night I measured the resistance of the 4 pairs of wires going into the clutches from the connector on the computer side of the unit. It is an 8 pin square connector. I couldn't see any number designation on the connector so I just used convention. With the ABS unit facing you and the computer removed the connector is easily seen and in the open. There are 8 pins on the connector 4 wide and 2 high. I numbered them starting at the top left. 1-4 on the top row 5-8 on the bottom. The pair of wires that were measured together seemed to go into the clutch unit together as pairs.

The resistance readings are as follows.
PINS
1-5 = 2.3 Ohms
2-6 =112.4 Ohms
3-7 =112.4 Ohms
4-8 =2.2 Ohms

I also measured the resistance of the computer pins to see which ones were at ground potential. The measurement was taken with the computer module disconnected. The measurements were using the computer module aluminum case as reference. The following pins had continuity to ground.
Pins: 1,2,3,4,6,7,11,16,17.

Thats all I have for now. I am still waiting for parts.

Jeff
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  #14  
Old 11-05-2007, 05:06 AM
voxmagna voxmagna is offline
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Re: Pics of ABS II Internals

So far my 'fuzzy logic' and ignorance of the 'clutches' says you have symmetry which is good.

Are you also checking the 'ABS Relay' in the right side relay box? I don't know what it does other than flash the warning lights, but with that diode gone, I'd make sure it's still working and hasn't got welded contacts.

When I last looked in there, most of the relays with 1 or 2 exceptions seemed to be of the same base pattern. You could just unplug the relay and check the switching and contact resistances on a battery.

I think a new diode might have fixed your ABS unit.
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Old 11-05-2007, 01:21 PM
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Re: Pics of ABS II Internals

Vox, After a futile wait for parts I decided to seal up, re-wire and bleed the old unit. Whats a Friday night without bleeding knuckles! The whole process from start to finish took me about 3.5 hours once I decided to re-install the old unit.

Short story: IT LIVES.

After the first reset I had the two blinking lights together I rolled it out to the drive and the warning lights for the self test went out. I was also able to permantly install a wire into the ABS connector pin 21 by threading it through the rubber protective cover to the back of the female side of the connector.

My best guess is that most units could be revived if there is not a catastrophic failure of any of the three systems (hydro,electro,mech).

To summarize what I did I will list the following steps. This only applies to a 2000 K12RS!

1. Evaluate the indicator lights and decode them. Make sure to take into account exactly when the lights go into the alarm mode. As soon as the key is on or at start up, for example.
2. Read the pulses off of the diag connector.
3. Examine all of the sensors, front and rear and insure the gaps are correct.
4. Check all of the fluid levels.
5. Check all of the encoder rings on the wheels for true runout.

If after all of these things are checked and indicate that the unit is still the fault (as mine did). The unit will have to come out and be evaluated.

The procedure to remove the unit is covered in the Clymer manual and worked well for me.

After removal from the bike:

I was able to gain acces to the side cover by carefully pushing straight up on the black plastic cover. It popped up and slid off with no breakage. The relay and wiring should now be documented and photographed if possible. The relay box contents are held in only by friction of a foam strip on the top of the relay and grooves in the side of the box. The relay comes straight out. Take care to not stress the 2 pin connector for the relay connector due to their small gauge. Once out of the box the relay can be removed from the base after backing off the two torx screws that hold the main power pins in the base assy. once removed the relay can be tested for proper function. There is also a diagram on the side of the relay to show pin assignment. The cover can be removed by gently inserting a very small common screwdriver under the edges of the relay cover and pulling up on the cover. Don't stick it too far under the cover and pry up on the cover or you will contact the internals and damage them. Once the cover is off it is possible to clean and inspect the contacts and proper function of the relay. I just used a small 12 VDC battery and an ohm meter. The coil will show low resistance and the points are normally open.

After the relay is verified, inspect the continuity of the base wiring and diode. The diode will have a VDC drop of about .6 vdc and should show open in the other polarity. This can be seen with a meter that has a diode check function. My diode was bad. A replacement was found at the local electronics store for $1.98. It is a common rectifier diode type, nothing special. Next, clean all of the contact surfaces on the base and re-apply the proper compound.

The mechanical piece has already been described in earlier posts. With the exception of the embarassing "antenna theory" it has all proven to be good. The base cover can be removed and installed back onto the unit without much trouble. Just be sure to clean the old sealant off of the cover and the unit base. Also, use just the minimum silicone sealant when putting it back together to avoid any internal contamination. Extra sealant can be applied to the exterior lip if you feel you need a better seal. The cover can also be gently hammered to hold the lip of the base again. Sealant MUST be used to protect the mechanicals from any contaminants. The top of the ABS unit has four threaded brake line connections and two bleed nipples. The bleed nipples are installed in a plug that also serves as the top of each piston/pressure regulator. The plug can be removed with a thin wall 22MM socket (I still had to grind mine off). I was able to remove all of the internal pieces by grasping a small nub on the top of the piston assembly with hemostats and gently pulling it up. This exposes the lower piston and the majority of the piston wall. I cleaned both assemblies with clean DOT 4 and "Q" tips.

The electronics were removed by using a Dremel tool to cut a slot into the security screws. This unit is connected to the case with 4 of these screws. It is protected by a rubber gasket. Be sure to protect the gasket surfaces. Pull the electronic unit straight away. There is an 8 pin connector that is the only electronic connection with the mechanical base. There you can check the clutch resistance described earlier. There is nothing you can fix or adjust in the electronic module due to the sealant covering the componants and the lack of any adjustment pots or pins. DON'T DO ANYTHING TO THE ELECTRONICS IN THIS MODULE!

Once you have checked all of these individual pieces and repaired or replaced any damaged wiring, relays or componants there is a good chance that your ABS unit will also live again.

Bleed the brakes until the fluid is clear and free of air and double check everything. This is a critical system and your life may depend upon how it works. If there is any question in your mind about the system, have it checked by the dealer.

Just to be clear: I am a not a professional BMW mechanic. I am just, shall we say "thrifty". This repair was done with the intent of saving money. It is working fine and passes all of the self checks. If you do this procedure on your unit I must state that you are on your own.

Bon Chance

Jeff
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Old 11-05-2007, 02:22 PM
voxmagna voxmagna is offline
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Re: Pics of ABS II Internals

Excellent!! Now you haven't told us that you hit (at least the rear) brake, got a skiddy, and the ABS pumped away and you got no stuck warning back again?

My concern is there are 2 issues. 1. The ABS computer does its diagnostics in a passive manner without actually activating the pump and if everything checks out there are no latched faults. 2. The stuck piston/ high pump current scenario which could only occur when the pump was active. So you need to cover both the active and passive fault situations.

I'm sure you will be OK, we've all learned a lot from your posts so thanks for taking the trouble to put some flesh on this curious piece of our bikes that costs a lot to replace. Yes you are right to add the Caveat - brakes and electronic safety systems need some experience and careful handling which is virtually impossible to put over on a forum post. I had to disect an airbag control unit once, they are also tricky, but then ABS units don't explode if you get something wrong!

Yes I know the re-install is a bleeding pain, but think of the $$s you saved and you'ld have had to do it with a boneyard unit. Now you could do the whole thing in a couple of hours. My clutch took all day, I went back a few days later concerned about balance and it took 3 hours to remove it!

What part were you waiting for, I thought just the diode was the problem?
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Old 11-05-2007, 03:36 PM
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Re: Pics of ABS II Internals

My driveway is hard packed gravel and works great for ABS tests. The unit works fine on both the front and rear. You can both feel and hear the modulations of the ABS unit as it works. I was reluctant to try the front but got a good result from a "hard squeeze" test from about 15 MPH. Straight line!
The antenna theory has made me reluctant to make far flung guesses but if I had to make an assumption based upon observation I would have to say that the ABS computer looks at the condition of the clutch units using the resistance values. The only other thing that it could "read" from the ABS unit itself would be the coil in the relay. If the computer sensed an open coil it would flag an error. The rest of the inputs would be based upon sensor feedback and timing of events. So, something NOT happening could also flag an error.

The parts I was waiting for were a relay and the relay base. I had also ordered a spare Hydro unit from a bike rebuilder in NJ but I am afraid it was a fraud.

Jeff
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Old 11-05-2007, 05:38 PM
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Re: Pics of ABS II Internals

Wow ! you're all hot to go.

I wondered how to get the ABS on the front. Although the first time I rode over gravel I found it scary and something I'd rather avoid.

My feelings also on the 'clutch parts'. I'm sure they need some electronic feedback to sense the end of piston travel or change its direction. It's hydraulically called a 'modulator' so that would make sense. But you couldn't find out unless you 'scoped those wires somehow whilst it was operating.

If you're happy on the gravel, I read it's something to do occasionally to reduce the piston seizing problem. For most riders, the ABS pistons probably sit there in the same position for years so little bit of excecise does no harm.
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Old 11-05-2007, 05:46 PM
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Re: Pics of ABS II Internals

I feel that the pistons getting some exercise once in a while would be good for the system. The most important step in keeping the ABS unit sound would be to change the fluid yearly without fail. Even in this unit that had been serviced on schedule the fluid was starting to darken. There was also residue accumulation in the ABS piston cyl.

I don't think that it was the primary cause but it couldn't help.
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Old 11-07-2007, 03:39 PM
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Re: Pics of ABS II Internals

great post. I just replacedd my abs unit but kept the core..will try to repair and test to have a shelf unit. I love my K12RS and hope never to have the same problem. Maybe my core will help someone in the future...
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Old 11-08-2007, 11:24 PM
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Re: Pics of ABS II Internals

great pics! I have a '99 RS- does anyone have a step by step guide to bleeding the rear brakes?

thanks!!

MM M5
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Old 12-05-2007, 07:43 AM
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Re: Pics of ABS II Internals

HI , I am french , and I have problem with my unit .

Ia am not able to check the uinit , and I have spent too much money to switch from one to other , to replace into my bike .

Is there a way for you to sell yours . ?
habib.fontanel-AT-gmail.com
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Old 12-06-2007, 10:34 AM
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Re: Pics of ABS II Internals

Quote:
Originally Posted by JW-Spud
To summarize what I did I will list the following steps. This only applies to a 2000 K12RS!

Spud and Vox - I have a '98 model, I thought the '98 and 2000 model had the same system ABS, am I wrong .
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Old 12-06-2007, 10:38 AM
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Re: Pics of ABS II Internals

I think that the 98 is the same unit. The electrical pinouts will need confirmed just to be sure. My info was from a 2000. BMW loves to make changes.


Jeff
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Old 05-23-2008, 10:11 AM
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Spud & Vox, Any thoughts on whether this procedure would work on 2000 K1200LT?

I have a 2000 K1200LT that keeps faulting. Im using an analog multimeter to check the diagnostic code and keep getting 7 needle fluctuations which I believe indicates the ABS unit itself.

I have flushed the complete brake system twice and have installed a reset wire into the ABS unit wiring harness so that it is permanently in contact with pin # 21 on the ABS unit; I ground pin #2 with the brown and blue wire on the diagnostic port, then using my newly installed pin 21 wire.....I ground it for an 8 second count after turning on the ignition. This resets the Alternating ABS lights to both blinking together on start up.

My first reset did not fail on Rollout and worked for about 20 miles,....I tested with aggesive front and rear braking at low speeds and the ABS was functioning properly.......

Then,...after about 20 miles,... the alternating ABS lights came back on. I reset 4 more times and each subsequent reset failed as soon as I began moving on the bike...within about 5-10 feet. Another sytem flush (the second) and a bleed of the ABS unit as well yielded no change..........immediate failure as indicated by returning to the alternating ABS lights within 5-10 feet of first rollout after reset.

I have not checked my ABS sensors or ABS trigger wheel / Rotor (Not sure of correct term) runout as I believe this would be a different code.

I am game to try anything.........but have no knowledge of diodes or testing procedures....have read your above tutorial Spud,.....and believe I can work through it but may need a few assists along the way.

first question is: Where do I find a test meter/multimeter with a diode testing mode?

Brian in Austin, TX
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Old 05-23-2008, 10:28 AM
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Re: Pics of ABS II Internals

Brian, It sounds like you may have to clean out the individual pistons in the ABS unit. It really isn't that hard. The hardest part is when you have to get access to the ABS unit mounting bolts. Once you have the unit out just take off the large threaded cap that has the brake line port in it (that has been removed and capped). Get a clean work surface and slowly remove all of the componants in the piston assy. Try to do only one at a time if you can. I found grime and contamination clear in the bottom of the piston. It is my best guess that the contamination was causing the piston to bind or stick thus causing the fault. Be very careful not to scratch the piston or the wall. I remember that some of the parts were teflon.
As far as the diode checker, any digital meter should have the function. All the meter does during the diode check is to introduce a voltage to the diode that should be enough to get past the threshold of .6 or .7 VDC of a forward biased diode. A diode is just a one way valve that lets current and voltage pass in one direction only. If you look at a diode it should have a stripe on one end, that is the Cathode side. For example if you put 1 volt dc on the cathode and ground on the anode you should read approx .7 vdc. That is that one way "floodgate level" that the diode uses to do its job. You wouldn't want to run a test like that without some resistance in the circut but it is a good illistration.

Also I had to grind down a socket to make it fit into the recess for the piston cap.

Best of luck.

JW
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Old 05-23-2008, 10:40 AM
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Re: Pics of ABS II Internals

Thanks JW,

Since I am leading a group ride through the Texas Hill country this Sunday,...I think I will wait until sometime next week to attempt this.

Any chance you might have a pic of the Piston port(s) and the contents of the Piston/bore assemblies?

Brian in Austin
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Old 05-23-2008, 12:40 PM
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Re: Pics of ABS II Internals

The pistons are shown with the internals intact in pic #15 of post #1 of this thread. I didn't take a picture of the empty chambers or the pistons alone. My mistake. It wasn't hard to remove the piston. If I remember correctly I gently pulled it out with some needlenose. You can also see the ball and spring in the first pic.

I agree, you might not have time before a ride this weekend. It is a job that requires step by step attention to detail and you don't want to make a mistake with your brakes.

JW
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Old 05-23-2008, 12:58 PM
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Re: Pics of ABS II Internals

Just a thought WildWest. Do you think that it would be possible to get to the top of the ABS unit and with all 4 of the brake lines removed, get a socket in there and remove the plug/ bleed ports from the unit without removing the entire unit? The reason I took mine out was because I wanted to evaluate the entire unit top to bottom in order to check the entire system. If all you need to do is clean the piston/modulator assy(We Hope). Doing it with the unit in the bike would save time. I remember the unit was tight and that there was wiring and a frame tube in the way of a clear shot. I just don't remember without looking at the bike. I am at work:>(. The key would being able to get that socket in there.

JW
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Old 05-27-2008, 11:29 PM
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Re: Pics of ABS II Internals

Quote:
Originally Posted by JW-Spud
Just a thought WildWest. Do you think that it would be possible to get to the top of the ABS unit and with all 4 of the brake lines removed, get a socket in there and remove the plug/ bleed ports from the unit without removing the entire unit? The reason I took mine out was because I wanted to evaluate the entire unit top to bottom in order to check the entire system. If all you need to do is clean the piston/modulator assy(We Hope). Doing it with the unit in the bike would save time. I remember the unit was tight and that there was wiring and a frame tube in the way of a clear shot. I just don't remember without looking at the bike. I am at work:>(. The key would being able to get that socket in there.

JW

I will take a look at this tomorrow. You mention grinding down a socket....any chance you have a pic of this?

Brian
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Old 05-28-2008, 10:23 AM
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Re: Pics of ABS II Internals

No, Sorry I don't have a picture of the socket. The reason I had to grind it down was because the wall thickness of the socket was too thick to get into the recess of the nut on the top of the unit. It looks like they made it so it would require a special tool. Imagine BMW doing that.



Jw
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Old 05-28-2008, 11:11 AM
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Re: Pics of ABS II Internals

Quote:
Originally Posted by JW-Spud
Just a thought WildWest. Do you think that it would be possible to get to the top of the ABS unit and with all 4 of the brake lines removed, get a socket in there and remove the plug/ bleed ports from the unit without removing the entire unit? The reason I took mine out was because I wanted to evaluate the entire unit top to bottom in order to check the entire system. If all you need to do is clean the piston/modulator assy(We Hope). Doing it with the unit in the bike would save time. I remember the unit was tight and that there was wiring and a frame tube in the way of a clear shot. I just don't remember without looking at the bike. I am at work:>(. The key would being able to get that socket in there.

JW

JW

I'm getting ready to try this,....If I am trying this with the ABS unit in place......do I remove the brake lines? or leave them in place? Also, Do I need to bleed down the complete system first or will the piston areas self seal preventing brake fluid from gravity flowing from the reservoir out of the now open points on the ABS unit?

Brian
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Old 05-28-2008, 11:04 PM
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Re: Pics of ABS II Internals

JW,

A few more questions.

1)-Are the pistons under the ABS unit bleed nipples?

2)-If I get a Socket ground down ....and unscrew the nipple(s)....will what is under the nipple be spring loaded and trying to fly out when I unscrew the nipple?

3)-Once I get the nipple off,...how do I clean out the piston area? Q-tips? flushing with a solvent? Wiping out with a rag?

Brian
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Old 06-02-2008, 10:00 AM
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Re: Pics of ABS II Internals

Hi JW, I have a 1997 original checkerboard K1200RS.
I am trying to read the fault codes but am unable to find the right connecter, can you please point me in the right direction.
Thanks, in advance.
Dick Boyd Scotland
My first post on this site
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Old 07-11-2008, 09:02 AM
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Re: Pics of ABS II Internals

Thanks to Jeff, I got up the courage to get into my ABS-II hydro unit, and after a year of no ABS I finally have a operational system. A year ago I went into the dealer, after I had changed the fluid in the system to have the fault diagnosed and cleared. I hoped by changing the brake fluid, once the fault was cleared the system would work. The dealer infromed me that I had a plunger failure, and that the system would fail again. In order to fix the problem the hydro unit would have to be replaced. He was right the system faulted out within 20 miles. The cost of the Hydro unit was $1900.00, so I went to Beemer Bone yard in search of a used unit. I have been on their list for a year and had no luck. I was told by the dealer that the hydro unit could not be opened up due to a high pressure spring lurking inside. Then I came across Jeff's post sent him a PM to clear up a couple of questions and decided to try a repair. Once inside I found that the piston for the front brakes seemed to be frozen in place, but after some coaxing I was able to free it up, remove it and clean it.The piston for the rear brakes was in much better condition. I followed Jeff's instructions, cleaned everthing then reassembled the Hydro unit. I have had a working system for the last 300 miles and I beleive that the system is 100% repaired. I wanted to pass on a couple of things I learned during my repair.
1)I have an LT and the work can be completed with the unit on the bike.
2)One of the brake lines for the rear brake has to be removed from the Hydro unit in order to gain access to the pistons.(If you remove the Hydro unit from the bike you have to remove 4 brake lines.)
3)Do not use a 12 point 22MM socket, modify a 6 point, the 12 point slips off the cap bolt covering the piston.
4)In order to apply enough pressure to the cap bolt covering the piston, the bracket holding the Hydro unit needs the long bolt from the foot peg bracket partaliy installed to secure it. (At least on the LT.)
5)Once the piston is removed you will notice that there are small screens in the plastic ring around the piston. I carefully cleaned them by submersing the entire piston in clean brake fluid and swishing it around. (I did not remove the plastic ring from the piston) The screens seemed to have a little gunk on them.

Jeff's proceedure covered everything else. Thanks again Jeff!

Rick
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Old 07-11-2008, 10:04 AM
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Re: Pics of ABS II Internals

Congrats., good work. Herb
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Old 04-12-2009, 09:50 PM
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Re: Pics of ABS II Internals

K12Rick / JW Spud

I am finally getting around to this....I've just been riding with no ABS on my LT. Got everything around the ABS unit removed this afternoon....forgot I would need to grind down a 22m socket to undo the nipples.

I am going to attempt the piston clean out while the ABS unit is still in the bike......I think I can even get both nipples out without actually having to remove any of the four brake lines.......I can just slightly bend the two brake lines that run across the top of the ABS unit.

Can you tell me if I need to drain the brake fluid off before I attempt to remove the nipples? Also, what should I expect when I get to that last thread of the blead nipple.....and the nipple is released.....will this thing try to fly apart?

Brian

Quote:
Originally Posted by K12Rick
Thanks to Jeff, I got up the courage to get into my ABS-II hydro unit, and after a year of no ABS I finally have a operational system. A year ago I went into the dealer, after I had changed the fluid in the system to have the fault diagnosed and cleared. I hoped by changing the brake fluid, once the fault was cleared the system would work. The dealer infromed me that I had a plunger failure, and that the system would fail again. In order to fix the problem the hydro unit would have to be replaced. He was right the system faulted out within 20 miles. The cost of the Hydro unit was $1900.00, so I went to Beemer Bone yard in search of a used unit. I have been on their list for a year and had no luck. I was told by the dealer that the hydro unit could not be opened up due to a high pressure spring lurking inside. Then I came across Jeff's post sent him a PM to clear up a couple of questions and decided to try a repair. Once inside I found that the piston for the front brakes seemed to be frozen in place, but after some coaxing I was able to free it up, remove it and clean it.The piston for the rear brakes was in much better condition. I followed Jeff's instructions, cleaned everthing then reassembled the Hydro unit. I have had a working system for the last 300 miles and I beleive that the system is 100% repaired. I wanted to pass on a couple of things I learned during my repair.
1)I have an LT and the work can be completed with the unit on the bike.
2)One of the brake lines for the rear brake has to be removed from the Hydro unit in order to gain access to the pistons.(If you remove the Hydro unit from the bike you have to remove 4 brake lines.)
3)Do not use a 12 point 22MM socket, modify a 6 point, the 12 point slips off the cap bolt covering the piston.
4)In order to apply enough pressure to the cap bolt covering the piston, the bracket holding the Hydro unit needs the long bolt from the foot peg bracket partaliy installed to secure it. (At least on the LT.)
5)Once the piston is removed you will notice that there are small screens in the plastic ring around the piston. I carefully cleaned them by submersing the entire piston in clean brake fluid and swishing it around. (I did not remove the plastic ring from the piston) The screens seemed to have a little gunk on them.

Jeff's proceedure covered everything else. Thanks again Jeff!

Rick
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Old 06-03-2009, 06:03 PM
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Re: Pics of ABS II Internals

I little speack english!
I need help!
K1200RS 97, fell on my side and the bright lights of the ABS what to do?
Plz / thx!
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Old 06-03-2009, 06:31 PM
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Re: Pics of ABS II Internals

Zuco, My best recommendation is to first find a friend or neighbor who speaks fluent english as well as your language to help you on this....the process will go much more quickly. Describing technical issues....diagnoses of potential causes, and then the repair is tough enough without a language barrier.

Second suggestion is to start a new thread about this with clear title explaining the problem briefly.

BC

Quote:
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I little speack english!
I need help!
K1200RS 97, fell on my side and the bright lights of the ABS what to do?
Plz / thx!
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Old 06-03-2009, 06:47 PM
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Re: Pics of ABS II Internals

Quote:
Originally Posted by zuco333
I little speack english!
I need help!
K1200RS 97, fell on my side and the bright lights of the ABS what to do?
Plz / thx!
Send to us...we fix..for you...
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Old 06-03-2009, 07:00 PM
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Re: Pics of ABS II Internals

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Send to us...we fix..for you...

BAK04GT is our official Bosnian emmisary.
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Old 06-03-2009, 07:57 PM
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Re: Pics of ABS II Internals

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BAK04GT is our official Bosnian emmisary.

Stvarno !
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Old 06-03-2009, 08:03 PM
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Re: Pics of ABS II Internals

....I feel worldly...
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Old 06-03-2009, 08:04 PM
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....I feel worldly...Or is it word-ly..duno...but.. "they all do that" Really!
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Old 06-03-2009, 08:10 PM
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Re: Pics of ABS II Internals

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....I feel worldly...Or is it word-ly..duno...but.. "they all do that"




and should be!

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Old 06-03-2009, 08:16 PM
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Re: Pics of ABS II Internals

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and should be!

..You could go into page translator and find it in here....want to help
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Old 06-03-2009, 08:23 PM
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Re: Pics of ABS II Internals

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..You could go into page translator and find it in here....want to help

Koristim prevoditelj, ali on prevodi doslovce riječi!


I use a translator, but it translates literally word!
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Old 06-03-2009, 08:59 PM
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Re: Pics of ABS II Internals

.....Da!

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Stvarno !
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Old 03-30-2013, 02:19 PM
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Re: Pics of ABS II Internals

Greetings ABSII experts....
My 99 K12RS ABS warning lights were wig-wagging a few weeks ago so I checked sensor gaps, bled the entire system and then reset the error using a friend's GS911. The reset worked and the system has been fine for two weeks and 250 miles of daily commuting. Last night the warning lights were wig-wagging again on my ride home. When I got got home and turned the bike off, there was what sounds like a motor continuing to run, even when the key is off. The runaway motor appears to be the motor on the side of the ABSII unit and can only be turned off by disconnecting the battery. If I reconnect the battery (key still off) the motor begins running immediately. I'm assuming the culprit is a stuck relay. If true, is that the relay that is in the box (with the secret sliding cover) on the side of the unit? Any thoughts? The combined wisdom of the forum would be greatly appreciated. Bad news; My GS911 friend is out of town for the week. Good news; I have a spare ABSII unit sitting on the shelf. Any step-by-step instructions on how to do a pin 21 reset without the GS911?
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