Gen 1 ABS not working after storage

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Frushlorton

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After bringing the bike out of hybernation, I took it for a short ride for an inspection. As I approached stopped trafffic and applied the brakes, I experienced something I had never felt on this bike, a lock up of the rear wheel. I went to a parking lot and yep, everytime I panic stopped, locked rear wheel.

I have checked and changed the rear pads (they were still a about 50 percent) and flushed the fluid. No trouble pulling the fluid and the piston retracted with no issues.

Just took a test ride and still same issue.

ABS light cycles on start-up and then goes out. No ABS light when riding or during hard stops. Any suggestions?

 
Run the full diagnostic checks on it and see what happens. (detailed elsewhere on this forum)

Most likely your ABS hydraulic block is frozen up and the spools are not moving freely anymore. Others have had this same situation. Unfortunately there is no outward indication fo thios being the case, just the ABS isn't ABSing.

 
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+1 to what Tom said. Let's make sure it is FUBAR first.

Unfortunately, nobody has been successful at servicing the hydraulic blocks yet.

Doesn't mean that it can't be done. We just haven't figured it out yet!

 
So, who's gonna guinea-pig an ABS assembly?

It WAS assembled, so theoretically, is should be able to be disassembled.

I'm in the same boat as Frush...no ABS for at least 3 years now. STILL waiting for some ingenious forum-ite to spearhead this endeavor and git'r'dun! :)

 
I replaced my original crapped out ABS pump with used one and it works fine. They appear on Ebay regularly in the $150-$200 range. Considering it's an $1100 part new that's not bad at all.

 
I vaguely recall that ionbeam was supposed to receive a "frozen" ABS block, but I do not know if it ever showed up, or if he ever got around to the autopsy. It was at about the same time that he became gainfully re-employed (for pay this time), so his free time is probably not quite as disposable these days. I'd gladly do the honors of a post mortem if someone wanted to send me their old ABS block. Or else maybe I can get the one ionbeam has, if he even has it.

 
Fred you get to do all the cool stuff. I will be an interesting thread if the discectomy happens. I would venture to say if the OP replaces his unit we should have doner.

Dave

 
Heh... I'm guessing that he's hoping for someone to figure it out before he replaces it.

Kind'a like Howie has been, for the past 3+ years. ;)

 
Heh... I'm guessing that he's hoping for someone to figure it out before he replaces it. Kind'a like Howie has been, for the past 3+ years.
wink.png
Don't know if I'd have done anything if I DID have the knowledge to fix it...

Have had a couple of "butt-clenching" moments with the brakes the last few months, and the bike stops amazingly straight with the CT on the rear!

It's probably saved MY butt a couple of times. :)

Am kinda disappointed that neither you nor Ionbeam has this scoped out yet. :(

 
Hope to run the test tomorrow. I seem to have a bit of time since retiring from the Air Force. Ned to get this done before the job interviews start and it's back to commuting.

 
The test worked as it should. There was a noticible difference in pulsing between the front and rear. The front was a hard pulse and the rear was a slight pulse and vibration. Is that normal?

 
The test worked as it should. There was a noticible difference in pulsing between the front and rear. The front was a hard pulse and the rear was a slight pulse and vibration. Is that normal?
From a person that hasn't done the test, but read the linked page in post #4.....that doesn't sound to me like it worked as it should have.

  • your helper will try to rotate the rear wheel; it should rotate for 0.1 seconds then stop, then rotate again 0.1 seconds on the second pulse
Did it rotate for .1 seconds, stop, then rotate again .1 second on the second pulse? If it had vibration or slight pulse.....it sounds to me like it maybe didn't pass the test and/or may be marginal. (I've been watching this thread as I'm getting the occasional ABS light these days on my high-mileage 2005 and may have to do this myself in the future)

 
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I think the results are encouraging that you managed to get the pump to activate. In the seized blocks that doesn't happen.

 
Sounds like a good time to get some clean fresh brake fluid in there! I know you have done it once before but now you have probably moved the 'old' fluid that was trapped in the ABS block.

 
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Sounds like a good time to get some clean fresh brake fluid in there! I know you have done it once before but now you have probably moved the 'old' fluid that was trapped in the ABS block.
Which begs the question, "If I want to REALLY clean out my brake system, is there some liquid concoction I can run through my system to REALLY clean, not just flush, but the clean the system?"

Something along the lines of having new caliper piston O-rings (to replace old ones that might get damaged by a clean, not just a flush) and run a couple of quarts of brake cleaner through the system to loosen up and remove any built-up or deposited crud, followed by a thorough flush and refill with DOT-4.

Perhaps a fill with brake cleaner, let the cleaner sit in the ABS block a couple of days, which might free up stuck spool valves, then flush and fill with the real stuff..

Anyone want to WAG for me??

FredW...Ionbeam...Odot???

 
Sounds like a good time to get some clean fresh brake fluid in there! I know you have done it once before but now you have probably moved the 'old' fluid that was trapped in the ABS block.
Which begs the question, "If I want to REALLY clean out my brake system, is there some liquid concoction I can run through my system to REALLY clean, not just flush, but the clean the system?"

Something along the lines of having new caliper piston O-rings (to replace old ones that might get damaged by a clean, not just a flush) and run a couple of quarts of brake cleaner through the system to loosen up and remove any built-up or deposited crud, followed by a thorough flush and refill with DOT-4.

Perhaps a fill with brake cleaner, let the cleaner sit in the ABS block a couple of days, which might free up stuck spool valves, then flush and fill with the real stuff..

Anyone want to WAG for me??

FredW...Ionbeam...Odot???
Howie, you're better than this. Brake cleaner is for external parts and has no place in the brake hydraulics. Simply flushing with fluid and activating the ABS is as good as it gets, and more than sufficient. The most likely culprit of ABS problems is old moisture contaminated fluid. Do the maintenance with fresh DOT 4, and it should never be an issue. When the fluid is flushed, it does exchange the fluid in the ABS blocks. There may be a small amount that doesn't flush through unless the block is activated, but it shouldn't be a problem.

(best WAG I got)

 
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