ABS problems?

[A2Z]

I was going to post about this a couple of weeks ago, however, I was waiting to hear back from the bike shop on their assessment as to why (?) before I did.
A couple of weeks ago, I rode my bike to Sydney. Just as I was trying to get back on the M2 for my return trip home, the ABS brakes locked up...right in the middle of the frikken entrance lane to the freeway, at 3pm rush hour. Couldn't budge the bike. Both wheels were locked.  Luckily, there was a construction site just across from me and I was able to get some help dragging the bike off the road...30 mins later. NRMA Road Service gave me priority response as I was on a freeway entrance...20 mins max, they said. So 3 hours later, I was abusing NRMA as it was now 6pm and I was still sitting there with no where to tow my bike as the bike shops were now all shut. So...to make up for it, NRMA towed me back all the way home to Horsley. Got home just in time for State of Origin (whew!)
I didn't have a chance to take the bike to my local bike shop to have the brakes looked at until yesterday (Monday). The brakes seemed to have freed up, but the ABS light was still on. So I decided to ride my bike to the bike shop (Trevor Jordan). The ABS lights went out a block from the house which made me happy. But then halfway to the shop, I could feel the bike being pulled up by the brakes. The ABS lights were back on.  I didn't stop as I was on the freeway and the shop was only 20 mins from home (and only less than 10 mins from where I was at this stage). By the time I got there, smoke was spewing from the rear brakes. On checking it out, my brakes were actually on frikken fire. Seems my brakes had worn right through the pads. I could also see the brake caliber sticking out.  This was only 5000kms since I had a service done. No way!
Since then, the bike shop has confirmed that the brake pads where in great condition, having only been replaced 5000kms previously.  Parts are on back order, hence the delay.  They are at a loss as to how or what happened with the brakes that would cause the ABS to lock up. As soon as the parts arrive (around July 15) and they put the bike back together, they'll do some test to see what may have caused the problem. 

Has this ever happened to anyone else?  Or have you heard of this happening?   

[Brock]

The ABS doesnt put the brakes on, it actually releases pressure to to stop wheel lock up (very simplified explanation).

I would say that there is an air / moisture  bubble in the system. As the bubble heats up, it causes the pressure in the lines to increase and makes the brakes come on. This generates more heat, and more pressure. You could have released the pressure by cracking the brake bleed valves.

Try doing a copmplete brake fluid flush, look in the manual (available in the ST1300 section ) for the correct bleed procedure.

[A2Z]

The ABS doesnt put the brakes on, it actually releases pressure to to stop wheel lock up (very simplified explanation).

I would say that there is an air / moisture  bubble in the system. As the bubble heats up, it causes the pressure in the lines to increase and makes the brakes come on. This generates more heat, and more pressure. You could have released the pressure by cracking the brake bleed valves.

Try doing a copmplete brake fluid flush, look in the manual (available in the ST1300 section ) for the correct bleed procedure.

Thanks for the enlightenment.  I have no idea...as you can see.  I love my bike, and I love to ride. But unfortunately, I don't have the skills or understanding to repair my bike. I can service it, fix a flat or attach farkles to it.  Anything more complex than that and I'm up shit creek. 

[Gadget]

What Brock said.

Also Brake fluid is hydroscopic, which means it absorbs moisture, so if the reserve tank seal is faulty, it will absorb moisture out of the air.

The moisture can then turn to steam if the brakes get hot.

 It is good practice to change the brake fluid regularly. That requires the correct bleeding equipment to remove any bubbles.

Bubbles of air create two problems, the first is spongy brakes, the second is brake lock-ups.

[A2Z]

Finally got my bike back from the shop.  It turns out the actuator in the front left brake calliper was stuck on which prevented the rear brakes from releasing.  Apparently due to corrosion.  I don't want to talk about how much it cost to fix as I don't want to start crying again.  But I'm just glad it's back on the road.

[Biggles]

Finally got my bike back from the shop.  It turns out the actuator in the front left brake calliper was stuck on which prevented the rear brakes from releasing.  Apparently due to corrosion.  I don't want to talk about how much it cost to fix as I don't want to start crying again.  But I'm just glad it's back on the road.

Any idea why it was corroded?  Anything we should be looking out for?

[A2Z]

Any idea why it was corroded?  Anything we should be looking out for?

All they could say was that this can happen simply due to age. I asked it it could have been dirty brake fluid but they reckon not in this case.

[Sicman]

Living next to the Pacific ocean may explain the extra moisture 

[alans1100]

Finally got my bike back from the shop.  It turns out the actuator in the front left brake calliper was stuck on which prevented the rear brakes from releasing.  Apparently due to corrosion.  I don't want to talk about how much it cost to fix as I don't want to start crying again.  But I'm just glad it's back on the road.

That sounds like the secondary master cylinder which is what activates the rear calliper. It's a mechanical linkage so maybe it pays to lubricate the linkage from time to time with RP7 or WD40 like I do on my 1100A.

[troy_s]

Hi All,
 Just got my 1300 returned from the workshop with exactly the same issue.Same shock regarding the repair cost but I guess thats just the nature of this hobby

The issue is that now I am experiencing what feels like the bike is having a minor epileptic fit. Engine is running smoothly so not an issue with fuel. Its like running over a series of small corrugations at uneven intervals. Is most evident when going at a steady speed.

 I have the mechanical aptitude of a wet rat with emphysema but im wondering if it may be related - possibly something that may cause the brakes to pulse on their own at uneven intervals. Showed the repairer who suggested that it may have something to do with the steering bearings although it was not evident prior to the surgery he completed.

thoughts please and appreciations for the same in advance.
 

[Biggles]

That's a completely new symptom on here.  In the context of working with the ABS system, I'd suggest it's a dodgy ABS module that's generating random brake pulses.  I'd imagine a new module would make a sensor that is being discussed elsewhere look positively cheap.  Can you afford to source a module from the wreckers?

[troy_s]

you are going to love this explanation
 Repairer replaced the silver bit that bolts on above the left caliper on the front - looks a bit like a knuckle duster.
 Is that what you are talking about?

[troy_s]

found the receipt
 repairer has
- replaced front left caliper mount combined brake
-remove rear caliper, supply and fit caliper kit
- blead complete system
- replaced rear pads

[alans1100]

you are going to love this explanation
 Repairer replaced the silver bit that bolts on above the left caliper on the front - looks a bit like a knuckle duster.
 Is that what you are talking about?

That sounds like the Secondary Master Cylinder (SMC) that was replaced along with new rear pads etc.

The module that Biggles was on about from his description is one of the ABS modulators of which there are two; one for the front brakes and one for the rear. Along with ABS computer they release and activate the brakes when a wheel lock up is detected.

I don't hear of to many SMC issues on the 1100A and I sometimes wonder whether the upgrade on the 1300 created more issues than they had on the 1100.

[Biggles]

you are going to love this explanation
 Repairer replaced the silver bit that bolts on above the left caliper on the front - looks a bit like a knuckle duster.
 Is that what you are talking about?

No, as Alan says, I was referring to the modulator.
So I trust the problem is completely sorted.

[troy_s]

Hi
Still a work in progress. Going back for more exploratory surgery on Friday