04/05 Flange defect, take note

Hi, new here and new to these bikes, do you think this cracking problem could be caused by the thread not being fully tapped thru on the reverse side? Because the thread is not cut to full depth when you screw the bolt in its like screwing a parrallel thread into a tapperd thread and this would cause a 'swelling or expanding effect on the lug, this would be compounded when the brake disc would be cooling down as the aluminium hub would cool quicker and clamp on to the thread causing further stress? Do you have a photo of the reverse side of the lug showing if it is a full thread all the way through, as one that ive looked at was not tapped full thread all the way through, the thread started to tapper in about 3mm short?. As I said new to these bikes and trying to prevent/cure any known problems I may come across.
 
2004 (registered 2005) 1200GS with less than 18000m under it's wheels.

flangeasmby.jpg


crack.jpg
 
Checked mine today,

2004 with 17.9k on the clock and nothing wrong with them FYI.

Sorry to hear youre's are not mate. :(
 
Expensive Paperweight

Wheel off, caliper off, disc off, circlip off.

Heatgun for a few minutes, tap off.

Heat new flange, tap on, rebuild with new disc bolts.

30 minutes.

:thumb2

Flange1.jpg
 
I take it my use of a 3-legged gear puller was unnecessary then and a simple hammer would have sufficed ?:nenau

I had to keep applying heat to keep mine sliding off the drive splines, if I stopped heating it would instantly cool and start to shrink back onto them.

Glad you got yours fixed, and easy enough DIY job and like you say, an expensive paperweight.
 
Spyke60

Thanks for the info on the cracked flange. I had a bit of a look while changing and fitting a new disc. Had another good look and behold, cracked lugs. I am also in the aircraft trade so am particular about torque loadings.
So it is interesting to see there has been a few other similar problems. i would put down to the casting. As a matter of interest when you fittrd your nrw flange did you use any anti seize of sorts

Keep the rubber down





Pukmeister said:
Perhaps, but I'm pretty sure I would have noticed it. My guess is brittle fracture but as I don't have access to a scanning electron microscope I can't prove it. The profile of the component has no obvious stress raisers and the two cracks have propagated along differing paths.

BMWRich58, I've been an Engineering Technician since 1982. I've worked on Gas Turbines and reciprocating diesels the size of a house and costing millions. I think I can be trusted to safely tighten a fastener or two on a motorbike. Of course I used a torque wrench and followed the instructions in the RepRom, I'm not stupid.

My local dealer has never seen/heard of this happening and took a look out of interest. Eyebrows were raised as the same flange is fitted to the entire R1200 range plus the K1200 model range. They asked if Michnus's bike had the stock disk and pads as mine are non-OEM.

They advised me to contact BMW customer services as a goodwill gesture is unlikely. I simply bit the bullet and ordered a replacement 'flange' under the new part number of C33.11.7.699.631 for £115.99+vat (£133.38) as the old part is no longer available ( I wonder why??).

Pity really as I am unemployed again at present so could do without the (unexpected) expense but my bike is my sole means of transport. No doubt pulling the flange from the splined rear hub will cause me some more headaches. Probably gonna need to put the FD in the freezer for a bit, then get the turbotorch out.
Click to expand...
 
Great, thanks. Another bloody thing to check before setting off on my wibbly wobbly trip in 2 weeks. I've always subscribed to the concept of the three wise monkeys but now you've got me worrying. Thanks, I guess.






Oi! Where's the f*cking hammer!?
 
May or may not be connected with the cracking of these lugs, but has anyone experienced this, bike on centre stand and at ambient temp check rear wheel for rock between 12 and 6 oclock and no visable play, go for a blast around and then carry out the same check but now the hub is @ 40 degrees (checked with thermal gun) due to the heat transfer from the disc and there is now visable play in the hub on the splined shaft, hub cools down and flange tight again. If this is happening and not being noticed every time you apply the brakes the pads are pulling on the disc that is 'loose' due to the hub expansion stressing the lugs. I tried this check 3 times once I noticed it and every time had the same result with the hub expansion. Normally you have to heat this hub to 100 degrees to disassemble it !! Forgot to say, this was on an 04 bike.
 
Yeah My mAte had a flange eat itself due to the crappy design and BM only gave him a partial payment!

Better than nowt but it's obviously a design / materials flaw as the item isn't removed in the service schedules!

photo 1 old one 18k

photo 2 replacement that didn't work because the drive splines were worn too!
 

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Jaythro said:
Yeah My mAte had a flange eat itself due to the crappy design and BM only gave him a partial payment!

Better than nowt but it's obviously a design / materials flaw as the item isn't removed in the service schedules!

photo 1 old one 18k

photo 2 replacement that didn't work because the drive splines were worn too!
Click to expand...

So I guess he had to have a new rear splined axle as well as the hub? What about the crown gear on the axle, new complete assembly or reused the original crown gear wheel on the new axle?
 
Second time around! :blast

Message via my website from ADVRider AldenB...

"Andy,
I had posted the 1st photo you used in your writeup (on the ADVRiders site as AJB1). Just to up date you and guys @ UGSer.com, while changing tires yesterday I checked the flange as usual and two of the lugs are cracked. Called the dealer and now they want the bike for a couple of weeks to show the factory rep.

Here we go again!
Click to expand...

Original cracked flange:
r1200_k1200_flange_cracks.jpg
 
THE DOCTOR said:
Wheel off, caliper off, disc off, circlip off.

Heatgun for a few minutes, tap off.

Heat new flange, tap on, rebuild with new disc bolts.

30 minutes.

:thumb2

Flange1.jpg
Click to expand...

I wish....took a three legged puller and shed loads of heating to get off, then going back on it got stuck (too little pre-heating I know!) and it took a genius engineer friend to point out the old flange was the perfect drift. Then saw the FD had been leaking all along anyway...dammit. Now all fixed and dandy though.
 
Same flange different crack location

New to Bikes and this forum. Just acquired a 94 GS in the Philippines and noticed cracking in rear disc flange. The cracks on my bike are on the lugs which secure the flange to the wheel hub not the disc. So when you are checking your bike look very carefully at the entire flange. Part ordered from BMW Philippines Php 19000 (£270) think yourselves lucky you're in UK.

Other than this and a few self induced niggles I'm loving this bike and my new found hobby. Great blokes to ride with too. Most have Harleys but I'm convinced I made the right decision with the GS -wouldn't swop em for anything else. Tried a Triumph Rocket III being a Brit and was very impressed at its smooth power on and off compared to my GS. please wait 2 seconds for an uncompressed image, or press Ctrl+F5 for original quality page
 
Great, cracks already

Just checked my 54 1200gs and I have a crack on one of the lugs. Only had the bike a couple of weeks.

Has anyone managed to get these done under warranty as I have a BMW 12 month warranty with the bike when I purchased it from Alan Jeffries BMW and if so what was the process for getting the warranty claim accepted?

Many thanks

Chris
 
Do not ride it again before you speak to your dealer. The part is specifically listed as covered by extended warranty, but only if you don't ride it after finding the fault. Garage should arrange to collect bike. Kick up a right stink if they don't. Endangering your pink body and wallet if you ride it. George
 
Rang the dealership today and it doesn't appear to be a problem warranty wise. They did say they have not heard of this failure before and seem happy for me to ride the bike to them for an assessment and to see if it's safe to continue using.
I will be going armed with the updated part number.
It will be interesting to see if they say it's not safe to use after travelling 40 miles to get to the shop. If nothing else I hope to get a loan bike as travelling home on public transport in full riding gear isn't an option.
 
don't worry too much guys, its perfectly safe with everything cracked all round... Unless you lose a piece from a couple of holes, there is no way the part can work itself loose... think abt it...

Technically, of course, its another piece of sh*te BMW underengineering to the altar of better profit margins. Realistically though there is no danger of anything happening. As long as it remains in one piece that is (one crack per hole)
 
Took the bike to Jeffries yesterday. New part on order and will be fitted whilst I wait. No probes with using it even tho the fault has been pointed out and realistically it's not going to fall apart (only one cracked lug).
Great service so far, very apologetic and more than willing to put me on a demo bike if the job takes any longer than the half hour they estimate.
All in all I'm happy so far.
Chris
 
Nippy Normans supply Touratech, Wunderlich, Desert Fox and many other makes of accessories.
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