WARNING rear brake disk mounting flange failure!

[Wazza]

My flange failure.
Hi, My name is Warren and I ride a 2005 R1200RT in NSW Australia, my bike has 77,000km's on it, I have had it since new and have had it serviced every 10 thousand.
The other night I was riding it to work when I heard a tick tick noise, thinking is was a stone in the tread I weaved to fling it out, it was still there so I started to slow down and at around 50km's hr I heard/felt an almighty bang/crash/grind. I thought the gearbox had dropped out. Upon Inspection i discovered that the rear rotor completely sheared off the flange where the cracks are shown in Aldens link "http://www.motorcycleinfo.co.uk/index.c ... eId=360814" and also 1 wheel bolt was also broke completely out of the flange, three other wheel bolt holes in the flange were cracked also as shown in Aldens link. I was very fortunate that this happened at a low speed as this could have been fatal on a faster weekend ride. I had wished I had seen the warnings signs (cracks) prior and I strongly recommend everybody who owns one with these BMW's with this model flange should check them regularly or replace them. Cost was $520 for flange, $220 for rear disc and $260 for labor. Thanks Alden for your information.

Good Luck
Warren

[Caroanbill]

My flange failure.
Hi, My name is Warren and I ride a 2005 R1200RT in NSW Australia, my bike has 77,000km's on it, I have had it since new and have had it serviced every 10 thousand. Warren

Before we get all het up again, read Don E's notes re changed part numbers and note year of this RT - 2005.

So far as I could find - all the ones that cracked were '04-05 models. BMW has superseded that PN 3 times according to the threads I read - and ours is likely the last revision. It was most prevalent on flanges with metal inserts for the wheel lugs - which no R1200R has ... I think the R1200R can be removed from the scare list at the top of this thread. We have NO reported incidents of it on this forum ...

Warren - I'd be interested to know who your dealer is. Mine is Procycles (both shops), although my last 10K servcie was done my Mick Owen in Canberra.

[KACUKBiker]

I ride a R1200RT 2005 Model in the UK. Just had a brake disc/Rotor problem and whilst inspecting it found three cracked brake flange lugs and one mounting hole for the rear wheel cracked through. From looking through the mighty web this seems to be a more common problem then one would expect.
Beat the hub off and will be taking it to the local dealer soon. Did not want to ride the thing like it was. I am am surprised this has not had a recall or at least a service warning. Potentialy very dangerous as no one would expect to look at this. My bike just had its annual test in the UK and they flagged up a rear disk/rotor problem which I now beleive has been caused by the craked flange. Surprised they did not see the cracks. How bad is this and why don't BMW do something to warn people at least?

[deilenberger]

How bad is this and why don't BMW do something to warn people at least?

Once again - this warning doesn't apply to the R1200R (the superior Hexhead!).. we don't have cracking flanges.

[R12RnHouston]

I just passed 48K on my ‘07 and have been picking away at service tasks. This morning, a few minutes into changing the final drive fluid, I discovered this on the rear flange… every rear wheel lug bolt hole is cracked, the one pictured here being the most severe. Only one of the bolt holes securing the brake disk is cracked. I’m just passing this information on out of concern for the safety of other riders here.

David

[cug]

This looks a lot like failures introduced due to too much torque applied and then the normal strain on the components is too much. Mainly because of the use of air wrenches which are set up for way too much torque, but are used in shops because of speed of assembly. Of course, I don't know whether that's the case for you, just stating experience from looooong ago ...

[R12RnHouston]

This looks a lot like failures introduced due to too much torque applied and then the normal strain on the components is too much. Mainly because of the use of air wrenches which are set up for way too much torque, but are used in shops because of speed of assembly. Of course, I don't know whether that's the case for you, just stating experience from looooong ago ...

This has been suggested by others regarding this failure. I've always used a torque wrench when I've r-squared the rear wheel; and the service manager at the dealer that has changed my rear tire a few times tells me no air-driven impact wrenches are used in their shop. However, I can't be certain what went on for the first 21K miles of the bikes life under the original owner.

[cug]

Yeah, you really never know if you leave a bike/car/... out of your hands in a shop. Even good shops often have some bad practices. And it also might not be wrong that at all. It just reminded me of the time when we saw things like that in a shop I used to work for right after school.

[R12RnHouston]

Yeah, you really never know if you leave a bike/car/... out of your hands in a shop. Even good shops often have some bad practices.

That to be sure!

[uncle BS]

many here have bmw diease. it 's primary sympthoms are the inability of the bmw owner to admit his bike has a part failure. the justification of a failure as --well nothing is perfect. in it's more severe forms bmw diease deludes the owner into thinking bmw is the most superior bike on planet earth.

bmw diease is quite rare and is mostly found in the ranks of bmw owners, you may have it if you have the inability to admit that your bmw ever has a malfunction or premature failure.

[deilenberger]

A FWIW - the replacement for this flange is now steel. There were enough failures like this with the aluminum ones that BMW changed the design. What they haven't done is issue a recall, which IMHO they should. I check mine every time the rear tire is off, and so far - 70,000 miles - it looks fine, but it is something to be aware of and check as part of normal maintenance. Installation of the steel one might be best left to a dealer. Unlike the aluminum one which could be heated and expand enough to easily drop right on the splined shaft, apparently the steel one doesn't expand as much, and can be a problem if it closes down as it's being installed on the shaft.

[R12RnHouston]

Thanks, Don. I have indeed decided to let the dealer handle this one. The parts are in and they were kind enough to agree to come pick my bike up at my home today and trailer it back to the shop. I've not seen the new flange (in person), but like you said I've read on other forums it's steel and of a slightly different design. Yep, just something to keep an eye on. Taking it all in stride and ready to get back on the road.