WARNING: If you have an ABS equipped bike, read this!

[TheJoker]

Guys n gals,

A completely serious post from me for a change.

Let me tell me what happened to me. I had my bike in to my local (non-BMW) shop to fit a set of new tyres onto ye ole' tractah, and I was really pleased. Rode the bike back quietly in the rain (new tyres + rain = slow). Parked the bike in the garage, and left it there till Monday morning when I took her out to ride to work.
All happy and dandy I do a couple of aggressive overtakes, and the bike performs flawlessly... yieehaa... I come to a 40mph section and I, as usual, grab a big handful of braking to slow me down to 40... only to notice that the ABS kicks in quite a bit extra... maybe it's just the new tyres... no biggie.
I up the speed after the 40-are and again all well...

... UNTILL...

I approach the next roundabout - myself and all cars around me - are slowing down but I am NOT SLOWING DOWN the roundabout is approaching... the cars in front are getting too close... NO BRAKES - NO F%¤&%ING BRAKES!!! The bike just "glides" on ABS... I can feel a few small pulses of braking kicking in - NO WARNING LIGHTS ON THE DASH...
... somehow I manage to scrub off enough speed and slot in between a few cars to make the roundabout. *pheeww*
I stop at the next safe place and do a quick inspection - I can't see any hoses broke, no fluid nothing..
I continue my journey carefully
A few miles later I get the same lack of braking power, luckily I was going slowly. Again I stop, this time for a more thorough inspection - and I find the problem.

It's a very simple problem. The thin ABS sensor cable for the front wheel has been positioned so that it has touched the brake disk and thus the brake disk has eaten through the (ridiculously) thin plastic on the cable.
The Sherlock in me is quick to draw the conclusions:
- The disk has caused the computer to recieve "strange" signals from the sensor.
- Probably trying to save my *rse from a spill, the ABS "brain" has decided that my front wheel wasn't turning and thus released the braking pressure rendering my bike without any sort of brakes!!!
- The "brain" on my computer didn't figure this out in some 4 - 8 miles or so I rode without brakes.
- When the "brain" finally figured that the signals coming from the wheel is "out of bounds" - it turned the ABS system off and flashed the "Brake Failure" warning light. - Way too late IMO!

Now, before you all start loading up your shotguns, fetch your tar-n-feathers, let's reflect why this happened.
- My garage is not a BMW garage, but they've serviced thousands and thousands of bikes - my GSX-R1000 previously - these guys aren't novices. They've seen bikes and they've changed tyres before. But the obviously refit the ABS cable in the wrong place
- BMW has made a braking system that relies heavily on one little thin cable and a single sensor. Not only that, the cable does not come with any warning texts, no protection, no clips at the crucial locations, etc.

In my opinion these two points have to happen together for this incident to occurr. And while I reckon that my garage could have made a bit of effort dealing with the refitting, I reckon the bigges problem here is the design by BMW. On cars you have 4 sensors and 4 wheels, on bikes 2 sensors and two wheels. On a car the other sides wheels act as a back-up for the system. On a bike you don't have a back-up wheel. Despite this BMW hasn't installed any form of assurance that the signals coming from the sensor (or my brake disk) are 100% accurate.
Nor have they installed any sort of shielding or protection for this simple cable, especially dangerous on a bike that's intended to spend time off-road.
Bad design IMO.


I hope this little "scare" story has brought this to your attention. I'm sure that this issue will never be a problem for more than 99% of all 1200 riders, but I do wish for all of you to check which way your cable has been routed. And when you take your bike to your non-BMW garage, please show them the attached PDF with pictures of how the cable should be fitted (and how it should not be fitted). Please find attached PDF and redistribute it as necessary. Thank you!


For what it's worth, I've spoken to my non-BMW garage and they, without any hesitation, agreed to replace the cable (ca £50 + ca £50 for labour) at my BMW garage. No fuss, no problems. I will continue to use them.

Happy Riding!

 

[nadeem]

Thanks for that Joker - a serious problem indeed...I'm getting new tyres tomorrow hopefully and I'll be checking when they re-fit...

 

[Cestria]

Must have been a brown adrenalin moment that one!
Pleased you are OK. Thanks for the heads up.

 

[Tricky]

scary...

without wishing to sound like Dr ABS Brakes (who could... ) I wonder if there really is a more basic design fault with the ABS/servo set up that BM continue to ignore/or fail to address. Please... am not advocating a conspiracy theory (as such) or a cover up but when is someone going to lose their life because of this (IMO) over complicated setup... if it hasn't already happened?

I have a non ABS bike but to be honest might have gone for the ABS/servo bike if I hadn't been on such a tight budget.

 

[The Machine Cat]

... Please... am not advocating a conspiracy theory (as such) or a cover up but when is someone going to lose their life because of this (IMO) over complicated setup... if it hasn't already happened?

It is probably easier to find statistics about how many lives were saved by an ABS

Thanks TheJoker, I will check next time...

 

[DodgyGeeSer]

Nice one Joker
Tyres are due a renewal soon enough... PDF duly printed...
Sure am glad you managed that roundabout!

 

[kdude]

Well you managed to scare the crapola out of me. I havn't had to touch my front pads or rotors but am on a second set of rubber with 24,000 kms on the clock. But at least i'm aware of a BIG POTENTIAL SCREW UP if the sensor is not fitted correctly. Thanks for the heads up !

Happy Riding! [/QUOTE]

 

[Deadskin]

NO F%¤&%ING BRAKES!!!

Glad your ok Joker,
But the Incompetence shown by that garage is unbelievable,
to let you ride away with a lead rubbing against the disc is down right
dangerous...

Name and shame

 

[pogo]

Thanks Joker for that warning,

I had a close look to my own bike,and to my opinion ,once again,BMW are not to blame.dont need to be a engeneer to see which way the wire has to take to be at the right place.It is obvious,and this cable dont need more protection or bigger size if the job is done the right way.Like on airplanes,or anywhere the security purpose is involved,a special attention must be payed when doing maintenance.Your mechanic made a BIG mistake,not taking care enought on that particulary spot.I cant figure what would happen if that failure would happen in other circonstances....anyway,congratulations for your good management of the situation


A+ Pogo

 

[Tobers]

"It is probably easier to find statistics about how many lives were saved by an ABS"


Since you asked, I was saved by ABS on Thursday. Pouring with rain doing a usual 40mph or so to Slough. Approaching a right-hander. Saw someone driving strangely down a side street towards a junction with the road I was on. Looked at that car to figure out what they were doing, but meanwhile the cars in front of me stopped to let someone in from a side street on the other side.

Turned my attention back to the road in front of me, saw a looming traffic jam. Instinct took over and I yanked the brake lever hard. No controlled squeezing here - your brain goes into survival mode. The bike just stopped. ABS pulsed about 4 times. This is in teeming rain on a right hander too. I'm pretty sure I'd have done down without the ABS.

And I'll take the criticism for unusually poor observational skills too Need some more tuition from RichieS the Zen Master of Motorcycling.

Andy

 

[Marty Hill]

Joker,

Thanks for the heads up. Made a copy of the pdf.

Cheers,

 

[Kropotkin]

I'm going to post this in the Dutch GS Forum, if you don't mind. I'll host the file on my website. If you have any objections, PM me and I'll take it down, but from the gist of your post, I'm guessing you won't mind.

PDF here : http://www.xs4all.nl/~daisy/GS/1200GS-incorrect-ABS-sensor-wiring.pdf

One question though: After your first brush with brakelessness, did you consider turning the ABS off, to see whether it would still work?

 

[Emoto]

Wow, that must have been scary!!!! Glad you're ok.

In thinking about this, it seems to me that we have all grown accustomed to the routing of cables and wires as having a very low level of risk associated with routing them incorrectly. The speedo won't work, or the fuel doesn't feed properly, etc. However, now that we have bikes with sophisticated control systems, the consequences for improper routing have also increased. I guess another way of putting it is: the more important the job is that a wire performs, the more important is it to treat that wire with appropriate care.

Now, this is all common sense, of course, but we don't manage to put it all together until some sort of incident like this points out the issue.

From a software development point of view, this incident is a failure mode that BMW did not write code to handle immediately. I think that writing a letter to BMW detailing the shortcomings of the error handling might have some benefit.

Speaking based on years of personal experience in software development, error handling is one of the areas in software development that is rarely all-encompassing. Subsequent software versions tend to handle errors that are reported back from the field that the developers did not anticipate. Getting this info back to BMW might cause a good safety update in a future release. Who knows, maybe it could even be downloaded into our current bike brains.

 

[rc46]

This is a great heads up, thanks for that. It seems like during your start up the computer should have seen a fault and warned you immediately?

I change my own tires and to me it is just common sense to take extra precautions with the ABS ring and the sensor to not bump it or damage it in any way. A poorly trained tire changing monkey could easily cause many other potentially fatal problems besides screwing up you ABS sensor. I have heard reports of improper axel torque causing wheels to fall off, damaging caliper pistons so there is no brakes at all. My point is that you have to trust anyone who works on your bike with you life. I prefer to work on my bike myself. I am also in the camp that feels the upside of the ABS system far out weighs any downsides. I have been saved a by it a few times myself.

 

[Pukmeister]

Well spotted Joker, thanks for the heads up, and glad to hear you are OK.

I think BWM should definitely be told about this one. They may know about it already, but if told they may be able to rectify it with an easy recall notice to fit new wiring clips or something.

 

[johnnybravo]

Cheers for the warning Joker, glad to hear you're OK. It's well spooky when the ABS fires off and you're not expecting it - even more so if it doesn't give you any brakes back, YIKES.

Just as a matter of interest, you say you're near Oxford, whereabouts? It wasn't you I saw going through Middle Barton yesterday evening was it?

 

[nemezis]

There has been a recently a recall for the BMW K1200S for rerouting this cable. First information was on 06/13/2005 an can be found here:

http://www.michaelbense.de/k1200s/forum/viewtopic.php?t=1072&sid=b0d29ad13ce45a0826aac5248ac7ef92

Scroll down for the picture, you see the fix done by BMW for the K1200S. It seems to me that this issue is well known.

nemezis

 

[Mr K]

I just replaced a front.
I have a local shop who will fit and balance a supplied tyre for £5 on a "loose" wheel.
Luckily as a mechanical incompetent I removed the RHS calliper (as you sit on the bike) to get the wheel out, so didn't disturb the ABS gubbins....

Phew!

PS Had a ride today and nothing fell off.....

 

[Tobers]

Just checked my bike and the wire was routed incorrectly. I removed the caliper and re-routed it as per the diagram.

Thanks for that!

Andy

 

[birdseye]

Thanks for the warning but I really dont see this as a BMW fault. The tyre fitters were negligent in not refitting the wheel properly. Just as much as if they hadnt tightened up the wheel nuts - and you wouldnt have blamed BMW for not having self tightening nuts, would you?

Trouble is, the fitters have cocked up but will anything happen to them as a result? Probably not, so they will go on cocking up. Why should they care?

Had a similar thing happen to me when the CV joint on the steering of my car was replaced under a recall and none of the bolts were tightened up. The result could have been complete steering failure. But I had to threaten the garage with legal action before they would discipline the mechanics involved!