Wheel bearing disintegrates - F800

Maybe BMW has two suppliers for the rear hubs. One got it right and the other didn't??

Can't say it was a bad batch of hubs since they span such wide spread of build dates. Don't think it was a bad batch of bearings since people have had them fail twice. My thoughts also rely on Woody's analysis so . . .

Always possible that they're making the hubs on multiple machines, and only one is out of spec.

My guess is that they are cutting them on a CNC lathe, and only checking critical dimensions once per hour, at best. If they don't use tool monitoring equipment, a worn or chipped tool will screw the dimensions up, and they won't know it until the next check. Or, if an offset is entered wrong (or not entered at all), dimensions would be out too. Or possibly, they just have to big of a tolerance on the print the machine operator is working off of....

Or, if they were made in America, the operator didn't even bother to do the checks. :huh

I am having my bearing checked while they replace my gas tank and straiten my bmw bark busters at the shop this week. I had mine replaced just before I went on my recent 3000 mile trip so I have about 4k miles on these new bearings with varying surfaces. This should give me a good idea if it is the bearings or the hub. My bearings were replaced with the new "red seal" bearings instead of the black.

^^ And what the hell does that guy mean about American quality checks? We have pride in our work and American machining and tools are some of the best in the world. Import steel is crap and precision tools made by the Swiss are for watches not engines.

Yeti,

Add my son's name to the list, TXMedic. He had his rear bearings replaced w/9K on the odo.

I think his bike was built in 9/08.

36 is only the number here (ADVrider), not world wide and I would argue that for just this forum (or even the world total) 36 is no small number when dealing with a problem that can fail badly enough to cause a crash. The number becomes more than "nothing" if the failure causes you (or more importantly ME;-) to kiss pavement. In matters of safety, based on manufacturing errors, anything above one or two is major.

The only "balance" that matters is a grenading wheel bearing can cause fatal damage and there are enough of them right here to be a major issue. BMW had better be working on this one big time...before someone owns a major portion of their revinue (read; makes a big dent in their liability insurance and reputation).

Just a reminder to all; this will NEVER happen unless the NHTSA is properly and objectively notified. No hearsay, agenda, or embellishment. Get the facts in so everyone will benefit from a proper resolution.

Link to file notice

I've added TXMedic to the list and added your link to the list too.

Thanks!

Transport Canada's Safety Complaint Link:
https://wwwapps.tc.gc.ca/Saf-Sec-Sur/7/PCDB-BDPP/fc-cp.aspx?lang=eng



I will do mine tonight...

Another good opportunity, if you've discovered the issue during a scheduled service: Describe the issue calmly and objectively and check the "I would like BMW Motorad USA to contact me" box on your service survey form. I get one of these every time I take my bike in for a scheduled service.

PS. I filed my notice with the NHTSA.

Rob in Seattle

500 characters with spaces MAX, arrrghhhh

How can I include any links and make a case with that limitation

I think that i will just call them tomorrow

Woody has edited his post and corrected the measurements. He had a typo in his math as Redhawk47 pointed out.
The new measurements for the disc side is 46.94mm .06mm/.025" smaller ID, to tight for a 6204-2RS-C0 bearing but not to tight for a 6204-2RS-C3 bearing.

The new measurements for the drive side is 46.97mm .03mm/.001" smaller ID just right for a 6204-2RS-C0 bearing.

Could this be what all this is about. The wrong bearing has been installed in some of the bikes on the Disc side. The disc side is the captured bearing and the crush is a little tighter, .001" tighter, requiring a bearing with more internal clearance like the C3 bearing. I know the dealer parts guy doesn't know, I called him!

Anybody know what bearings the dealer is using when they replace the bad bearings????
I wounder if BMW is fixing the problem without telling anyone. I guess we will find out in time.
LaPorte

Wouldn't that just figure!!

So I wonder if you're correct. Is there a way to tell with removing the bearings? i.e. if I pull my wheel and remove the seal, would I be able to find something telling me what size my new bearings are?

When I call the parts guy at the BMW shop. He first look on the computer to see if he had the bearings in stock. He said he had one in stock. Put the phone down and went to retrieve it. He looked at the bearing and told me the number 6204LV. I asked if there was any more to the number, he said no. He was aware of the C0, C3, C4 suffix number and what it meant. So I don't know if he was looking at the bearing or the box it came in. But in bearing tables, like I posted, there are bearing made to have more free play to compensate for tighter fit's. So now it's time to find what bearing is supposed to be installed in the disc side hub bore. My guess it should be the C3 or the C4 bearing.
Maybe if you pull your wheel and pop out the seal you might see the number. I have seen some bearings with numbers on them not sure if these are stamped.

LaPorte

I'm putting a new rear tire on this weekend so I'll take a look when I do.

Rear Wheel Bearing Repair and Replacement BMW F800GS
Build date 07/08, 8800 miles
<o> </o>
After following various forum posts and reading Woody’s description of the wheel he repaired. I removed the rear wheel of my F800GS motorcycle Sunday to check the wheel bearings. The left (disc) side felt rough and notchy. The right (drive) side felt notchy too, but less than the left. I couldn’t tell if it was transferring across the wheel through the spacer. The bearing in the drive sprocket hub felt smooth.
I disassembled the wheel and measured the bores and bearings and found a press fit of 0.003” tight, on the left (disc) side and a press fit of 0.002” tight, on the right (drive) side. Both bearings felt smoother after they were removed from their bores, however sight roughness was still apparent in the left bearing.

I honed both bores to achieve a press fit of 0.001” (N7) tolerance to new SKF 6204 2RS bearings, heated the hub to 200&#730; F and installed the disc side bearing and snap ring and then repeated the heating on the drive side and installed the drive side bearing. When cooled and seated the assembly rotated smoothly and correctly with no feeling of roughness. <o></o>
I filed a report with the NHTSB and received confirmation yesterday.
I haven't talked to my dealer yet.
<o></o>
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Damn.... you want to fix mine if I ride on out there to CO? I'd do it myself but I don't have the tools or skills for that kinda work.

This is what aggravates me the most about BMW, there is a problem, and a forum has to figure out what it is and how to fix it. All the while the local dealer knows nothing about it and BMW will not talk about a problem or the fix.

Doesn't give me a warm fuzzy feeling when spending big money for a beta bike.

There are now three of us with 7/08 build dates on the list. :huh

Can you explain how you did the honing? I have talk to a couple of machinist. One of them does a lot of fab work on bikes. They are not sure how to do the work with the complete wheel intact, (hub, spokes, rim). Did you do the work with a hone and drill motor?

LaPorte