BMW F800GS rear wheel Bearing failures and solutions

folks this is sooo weird reading your remarks in another thread that i can't respond to,,,,BUT can lurk on.....

so my dear comrade wscollay FYI...i have NOT hammered on you on anything ,i NEVER called you a dope,,i simply used your post regarding the second bearing R&R incident and on your way to another one just like it as an example of what happens when one blindly ASSumes that simply replacing failed components is going to cure your problem,,,,you just assumed you had a bad bearing..most folks would probably do the same thing... it is like ''the Love canal incident'30 years ago,,the individuals in the neighborhood just thought they themselves had an anomally,,their own personal little incident....'twas only from a different perspective and some carefull analysis that th e''light went on'' and folks started realising ...WE HAVE A PROBLEM ON OUR HANDS!!!,,get it????

ALL of you can replace your bearings whether chinese ,taiwanese,czech,made in USAor whatever ...the will ALL suffer the same fate ,,,,provided they have the same tolerance as the originals,,,,

when Al Van Dyke was in the shop i showed him the Koyo bearing book with the different tolerances C1,C2,C3 etc,,, each one had a greater free play as the numbers went up.... there could be a possibility that BMW is replacing your old bearings [which FYI coincidentally felt very,very tight aka C1, then the more commonly used C3s] with C4s C5s or kinda like putting a looser band aid on the wound,,

i was simply pointing out that by the time [circa a month after tmex's thread started was when i accidentally saw this thread],,,i was pulling my hair out because so many of you had jumped on the 'bad bearing' bandwagon..and started switching out bearings,,,and then BMW started switching out bearings for you all,,under warranty no less....OK you get to start out over with new bearings ,,,,
BUT YOU ARE DESTINED TO SHARE wscollays fate somewhere down the line....because 'wrong cause will always =wrong effect'

hey ,,,it's mother natures way of pointing out what works and what doesn't,,,

so ALL OF YOU WITH NEWLY REPLACED BEARINGS OF WHATEVER BRAND OR COUNTRY OF ORIGIN>>>>

KEEP CHECKING YOUR BEARINGS!!!!....

OFF the BIKE!!!!!!

[ the damage is too subtle to tell in the early stages when it could avert disaster if ya just spin the rear wheel on the center-stand],

and YES,,,with a finger inside the bearing and press and twist..you'll have your answer immediately

nuff said for tonight..

w
OBTW...the ''speculation'' phase lasted until empirical data was actually gathered and collated.
Had we done this before this morning 2/3rd of the posts would be mute....

Another item,,,perhaps the one i measured was an anomally,,,based on the evidence ...it's just the tip of the iceberg.

here's the evidence....




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Gnarly Adventurer



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</td> <td class="alt1" id="td_post_11124564"> <!-- message --> Just to remind you guys, I believe I was the first F800 owner to experience a wheel bearing failure at speed. 70 fricken MPH!:eek1

I almost soiled my RP2's It isn't really funny though

My bike sustained damage to the tune of a new swing arm, hub, rotor, rotor bracket, abs sensor, axle, abs ring and of coarse the bearings were toast.

About $5000.00 with labor

My bike was fully loaded down for 2 weeks camping and riding in Colorado when this happened.

The bike was a real bitch to control and it damned near high sided me off of the mountain pass. ( I was coming down)

Check your bearings often!

Glen
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or tmex...






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Quote..."Yes. I was traveling much slower than RC (maybe 40-50 mph) going through a left hander when mine let loose. I had an anxious moment or two getting the bike stopped and off to the side of the road, and I do ride like a ballerina. This failure could be very serious if it occurred at speeds near triple digits. Be careful out there until this situation gets resolved.''

*********************************************************
or what's with these dealers??? i ask???
what's with these dealers????
and the advice they give or NOT give:huh:huh:huh:huh:eek1:eek1:eek1:eek1

BWOE......

<table id="post11098528" class="tborder" align="center" border="0" cellpadding="4" cellspacing="0" width="100%"><tbody><tr><td class="thead" style="font-weight: normal;"> 10-11-2009, 10:10 PM <!-- / status icon and date --> </td> <td class="thead" style="font-weight: normal;" align="right"> #544 </td> </tr> <tr valign="top"> <td class="alt2" width="175"> Bayner <script type="text/javascript"> vbmenu_register("postmenu_11098528", true); </script>
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</td> <td class="alt1" id="td_post_11098528"> <!-- message --> It seems some dealers are funny that way. I had an obviously chewed up bearing in my hand when I talked to my dealer. I wanted to know if he had to replace the bearing (again) himself to maintain the warranty or not. He said he was fine with me riding on it if I was ok with it. Warranty was no problem down the road either.
What amazed me most was how little he seemed to care about the matter. For straight revenue I would think these dealers would be swapping out any bearings that were remotely suspect, especially those that are failing at low mileage. And it's a fine line from a liability standpoint every time they have a wheel off to not be spinning the bearings to double check things are fine. Maybe once they've found a few more gone south in my area he won't be looking at me like I'm fucking retarded next time I walk in there....(but I won't hold my breath!)
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or????? <table id="post11125828" class="tborder" align="center" border="0" cellpadding="4" cellspacing="0" width="100%"><tbody><tr><td class="thead" style="font-weight: normal;"> Yesterday, 08:51 PM <!-- / status icon and date --> </td> <td class="thead" style="font-weight: normal;" align="right"> #589 </td> </tr> <tr valign="top"> <td class="alt2" width="175"> Roonie <script type="text/javascript"> vbmenu_register("postmenu_11125828", true); </script>
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</td> <td class="alt1" id="td_post_11125828"> <!-- message --> Quote:
<table border="0" cellpadding="4" cellspacing="0" width="100%"> <tbody><tr> <td class="alt2" style="border: 1px inset;"> Originally Posted by johngil
I dropped my wheel of at the dealer today. I don't like the feel of the bearings, but I'm sure they will say all is well.
I borrowed a bearing tool and will replace the bearings if my dealer doesn't do anything.
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I took mine in too as they felt gritty. The dealer said no failure yet so they can't replace them. If they had failed or there was significant movement in the wheel then they would replace. I pointed out there was no lubrication and the gritty feel. No luck.....
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does it have to FAIL FIRST???,,do we need a fatality or?????

folks tell me what i am missing in this conversation....

What kind of connections do you have with BMW, Woody. We need someone other than us "peasants" to start pushing the issue...

I have been following this thread from the start. It is great that people have dedicated so much time to find out what the problem is.

Would it be possible to spec a smaller circumference bearing instead of machining the hub?

I am no expert but have worked on heavy equipment most of my life and this seems plausable.

If I am thinking in the wrong direction I apologize.

Thanks Woody and Everyone for all their efforts!

Woody... what would you charge to fix this issue if we sent you our rear wheel?

Thanks a bunch Woody...good to have someone with your skills looking into this. I'm laid up and rides must be kept to commute but when the wheels need a beefing up, this rider knows where to turn.

Yah woody. Thanks a ton!!!
(A machinist buddy actually suggested going with a c4 bearing but I couldn't get a double sealed specimen)

At my local dealer I honestly feel like someone would have to die for them to give a crap. They certainly would not investigate the cause, they're too busy for that when they can just blame it on your riding, or the conditions or whatever they come up with. I don't find they give a flyin frack unless the stink you are raising is likely to deter some sap who's about to open his wallet to shell out for a new ride. Then you're suddenly the squeaky wheel...
I wish I had better experiences to relate.
Corporate will only care when their bean counters tell them it's become an issue.

Woody will be in and out of computer access for the next two weeks. He's out in the boondocks on his Vermont farm winterizing it. So if he does not respond immediately, that's why. If you need anything from the shop or have any questions, feel free to e-mail: woodyswheelworks@gmail.com or call the number below.

Thanks,
Chris

I have a F 800 S in my rental fleet that has been in the shop for the last two months waiting for a new hub, swingarm etc. A rider dropped it off after a rental and when I went to move it , it wouldn't roll. Thank god he made it back. At first they wouldn't warranty it because the bearing was a wear item but after I pointed out that at the 24k I specifically told them there might be some problem and to look it over and also change the belt, they agreed to warranty the problem. I'm still waiting. I think I'll have Woody check my 800 GS. Has anybody seen this problem on the F650 twins?

I've been compiling a list over in the "Wheel Bearing Disintegrates" thread over in Beasts. Thus far, only one 650 twin owner has come forward with a failed bearing. Since it's a different hub (entire wheel actually), hopefully that was just an isolated incident.

hi inmates,,,just got to the first hi speed computer in the last few weeks,,,wheeew what a difference some DSL service makes

perusing the recent posts in Tmex's thread makes me want to pull my hair out...ok,,,here's some more clarifying info...

1,,FYI,,a consistent rule of thumb for setting up/checking bearing/ bearing bore clearances is .0005'' of crush per inch of bearing diameter...

2,, so get the bore correct,,and then figure out the bearing race /ball clearances optimal for your application,,the majority of bearings used in the motorcycle kingdom are C-3...i do not think that chasing down extra loose bearings is the answer in this matter...IMHO correct the mistake ie too much crush and install the correct specifed bearing ,,that way we are back to the original game plan

3,,,i read the master machinists POV regarding man's ability to shave off .001-.003'' of aluminum... a good machinist can do that in a mill any day..and some one with experience can use alternative methods to remove the offending material...the trick is to do it concentrically AND laterally even.

4,,FYI most sheets of paper are .002''+/- .001'' so we aren't talking about a lot of material...having accurate gauges is paramount in not removing too much even by hand sanding/honing.. setting up the wheel in a mill shouldn't be a problem,,, and of course it can be even done in a lathe[unfortunately this requires unlacing and re-lacing/truing],,,,,the trick is getting ALL the way down in the corner and not developing a taper in the corrective process

OBTW,,,it is do-able if you have the tools and skill-set to attempt it!!!!,,me??? i just had a flash of an adjustable reamer we have in my other shop...the perfect tool for shaving off a .001'',
5,,when i read GJGSRider's post #731 form the Tmex thread i yelled HOORAY ATTABOY

Why,,because he took his time,,had the measuring instruments and coincidentally had the exact same anomallies and measurements that i came up with in my analysis several weeks ago...textbook...okay okay we had .0005'' difference on one measurement... i reprinted it below for your perusal

6,,,again,,,for your and every ones sake...
PLEASE,,,,for starters report these incidents to your dealer,,,I'm not a terrible big fan of recalls provided the manufacturer :
1,,steps up to the pump and shares what's going on with his product
2,,notifies his clients promptly
3,,tells them what to do,,ie ''DO NOT RIDE YOUR Motorcycle till we put the replacement parts in'',,,, or the appropriate warning/remedy
4,,fixes it ASAP with the least inconvenience/cost on the customers part

Here's my take on this whole issue,,,,

1,,i am convinced that you and me as consumers can appreciate that mistakes could be made in the millions of steps needed to get the products we buy exactly like the designers envisioned them,,,whether BWOE it's a material speced wrong or a machinist removing too little or too much off an item,,,

2,,i believe we would much rather have the manufacturer have the cajones to inform us of the problem and what he intends to do to correct it as well as the risk factor involved in continuing to use this product with the defect.
BWOE,,,"we've experienced riders complaining that their front axle is snapping,,PLEASE cease and desist from riding your motorcycle immediately!!!,,continuing to do so could result in a crash that could kill or injure you and others!!!!,,,make arrangements with your dealer to have it checked and repaired/replaced with an improved axle....it can be readily identified by this mark,,,there is no cost for parts and/or repair/replacement etc,etc

3,,i KNOW that i want to TRUST my manufacturer to have my safety be a higher concern than revenue losses or loss of image,,,being in a consistent state of denial is not conducive to developing trust and confidence amongst the believers in the marque when we bring our problems and complaints to the service department,,,and more often than not be greeted with the worn out mantra 'What problem????,,,there is no problem!!'

4,,i also know of the tremendous pressure that manufacturers are under when dealing with societies like ours that have certain elements waiting in the wings to capitalize on their mistake,,,i've written about it before and i'll say it again,,,,the pressure of litigation and being drawn into court scares the hell out of most of us....one is tempted then to weigh the cost of loss in revenues and your reputation against the costs of litgation or a recall

5,,i am convinced that in the long run we will want to be repeat customers of dealers and manufacturers that play it straight with us,,,that listen to our concerns,, and CREDIBILITY is one of our biggest concerns

6,,,i am convinced that the costs will be far greater should someone get injured or killed due to the recalcitrance of informing us of defects ,,,,the legal beagles are waiting in the wings for these kind of scenarios and our juries are especially benevolent when they hear that a manufacturer had the info and knowingly pretended all was well,,,then there is always the karmic debt that is incurred.....hmmmnnn we'll see how this plays out

woody


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carver



Joined: Nov 2005
Location: Wcolorado
Oddometer: 24



</td><td id="td_post_11240858" class="alt1"><!-- icon and title -->Add me to the list
<hr style="color: rgb(87, 87, 87);" size="1"><!-- / icon and title --><!-- message -->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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just got finished posting this in my parallel thread..

www.advrider.com/forums/showthread.php?p=11445224#post11445224

there's daylight at the end of the tunnel at long last

woody

WOW,,,,i can see that you are taking this seriously,,,,thanks for all the drawings etc


ok,,,,so far everything you did seems copesetic...got lost a lil bit on what you were hammering on etc...ideally we do not want to hammer on the inner races during installation,,,,using that big socket is ok or just reusing the old bearing/outer race as a drift works just fine too if ya have to tap the bearings in,,,the important part is not cocking the bearings ie tapping too much on one side....

ideally this can all be done with an alignment tool [i use the axle]and press or just with the heat n freeze method which ideally requires no tapping

the fact that the center spacer is longer than the bearing seating surfaces on hub bodes well....the crush factor problem is theoretically eliminated..however....

NOW here's where i think your theory about excess loads will be accounted for and explained,,along with our solution [ie if i understood what you were trying to say]

FYI,,,the bmw set-up is the type/design where they use one bearing held in place by a circlip or large nut...this bearing does the locating and essentially makes sure the wheel has very little lateral movement...in this case they have abs rings and a brake disc that they want to keep maximum control over,,,the opposite bearing is usually allowed to free float a bit

the 2 ways you can easily put too much pre-load on these bearings is by either
A...installing the sprocket side first and seating it in as far as it goes and then installing the disc side bearing all the way til it seats,,ya have to on this side or ya won't get the retaining clip in..this will automatically put a pre-load on both bearings

or,,,,
B...installing the disc bearing first with its retaining ring and then tapping the sprocket side bearing in all the way on the outer race,,,both ways will put tension on the whole set-up,,if you were to put your finger in the inner races and turn them,,, the odds are they will feel notchy

i ALWAYS check for this and apply this remedy

Rx= drop your axle in from the disc side...you can use your axle like a slide hammer or just get a hammer and give the end of your axle a little rap from the disc end,,the sprocket sides bearing's outer race will move toward the chain a tiny bit and unload/free the pressure,,,VOILA,,,your bearings will not feel crunchy any more

UNLESS of course you have the undersized bore....

this morning i had another flash regarding your notion....and how this pre-load we are talking about and experiencing can exacerbate the problem

like i said earlier,,i ALWAYS check that the bearings are turning smoothly after performing a bearing R&R...that's our goal...

now in a perfect world if the bearing bore were machined with the appropriate crush,,that little bit of pre-load wouldn't be a problem because the ''loose'' bearing would simply move over enough to achieve free-play....however if the bore is undersized then it will be more difficult to relax and align itself ie it will be under pressure from 2 directions,,laterally from the outer races being crunshed by us from tapping em in too far,,,and longitudinally from the crush of the undersized bore....and since the disc side bore is routinely smaller than the sprocket side,,, it will and does fail first.

in the diagram below ideally it should end up

1,,disc side,,, no space between retaining ring and bearing as well as bearing and the outer race seating surface in line with the edges of the inner/outer race and spacer,,,,because this bearing is supposed to locate/lock lateral movement

kind of like ya had in your first diagram



2,,sprocket/chain side,,,,minimally .010-.020''space between outer race and the seating surface on the hub,,,ie this is supposed to be there so that you won't ever crush /pre-load the bearings when you tighten your axle nut..HOWEVER the TRICK IS TO END UP having the outer and inner races of this bearing run in the same plane ie without a lateral load on them

3,,,all the inner races and inner and outer spacers will end up being jammed together when you tighten the axle nut

Bluebull2007,,,perhaps you can modify your drawing to depict what i'm saying...the finished drawing should depict the inner/outer bearing races being in line with each other and a lil space between the outer race of the sprocket side bearing and the seating surface of the hub

what is depicted here is the pre-loaded bearing ..it would be more accurate if the disc side had no space between the bearing and retaining ring and if the inner end of the races and spacer lined up
do ya see what i'm describing???




so there ya have it,,,,a lil fine tuning our understandings regarding "WHAT"S REAL-ly ''going on in there....

OBTW,,,your outer seal got distorted when all the bits and pieces packed up behind it and puked,,,,regarding your spacer,,,it may or may not have had the little positioning ring on it,,hence your spacer drops down and makes it harder to slip your axle through..it's not going to hurt you technically provided it is .010-.020' minimally longer then the bearing seating surface in the hub

woody

and you can x-post this to the tmex thread

Bluebull,,,FYI i'm LOL because most everything in this last post was essentially said before in the very first post of this thread,,unless i'm missing something...this time the spotlight was placed on the issue of the lateral pre-load and the deleterious effects it can have...go re-read and see if you catch my drift...

same to you and your beloveds...w

so i was just lurking on the tmex thread and came across this post from Red Hawk47 and his reply along with Joel Wisman's explanation of the factory tool ......FYI,,,i spent half hour talking with Bob at RAD about fine tuning the F800GS billet hubs and making doubly sure about the sequence we wanted to use to insure zero pre-load on the finished bearing,,

here's what we agreed upon,,,because the same technique will provide all of you with a bullet proof way of assembling your bearings the way they were intended to operate and that is:


A...for the disc side bearing to control lateral movement we want it pressed tight against its seat and held in place by the circlip


B...the sprocket side bearing's outer race is to free float while the inner race should rest tight against the inner spacer with no preload..we can accomplish this goal ideally by:

Rx...having 2 flat faced drifts shy of 47mm od circa at least 2 inches long ready to use [i'll get some pics of these later]

1...heating the hub while the bearings are frozen,,,then dropping the bearing side in first all the way til it seats and here's the trick,,you need to take the 47mm flat tool and tap the bearing to make sure it is seated,,

2...then stand the hub sprocket side up on this flatfaced tool

3...insert the spacer with centering ring down toward the disc side

4...drop the next bearing in and if necessary tap it in place with the second flatfaced tool

5...let it cool so that the hub shrinks and grabs the bearings

6...flip over and install the circlip with the sharp edge facing outwards

7...install the disc seal

8...check your bearings they should be perfectly located and spin free

there ya have it...tis the proper sequencing AND use of flat faced installers that will give you consistent results..of course in a hub properly bored

woody

<table id="post11751348" class="tborder" align="center" border="0" cellpadding="4" cellspacing="0" width="100%"><tbody><tr><td class="thead" style="font-weight: normal;"> 12-30-2009, 07:06 PM <!-- / status icon and date --> </td> <td class="thead" style="font-weight: normal;" align="right"> #827 </td> </tr> <tr valign="top"> <td class="alt2" width="175"> RedHawk47 <script type="text/javascript"> vbmenu_register("postmenu_11751348", true); </script>
Adventurer



Joined: Oct 2006
Location: Berthoud, CO
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</td> <td class="alt1" id="td_post_11751348"> <!-- message --> Quote:
<table border="0" cellpadding="4" cellspacing="0" width="100%"> <tbody><tr> <td class="alt2" style="border: 1px inset ;"> Originally Posted by JoelWisman
Bluebull2007, the factory tool we use to install bearings has a projection in the center that fits the bearing inner hole and is flat all the way across to apply pressure squarely on both the inner and outer races simultaneously.
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This is the key to alleviating your problem Bluebull2007. The right side bearing is intended to "float" in it's position in the hub. It looked like you used a socket to press the bearing in - that presses the outer race only. By using a solid tool the presses both the outer and inner races the bearing will stop at the sleeve and the outer race will be in the proper "float" position.
<!-- / message --> <!-- sig --> __________________
Dan

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What I don't get in all of this, is that this bearing arrangement, one being retain by a circlip the other floating with a spacer in between, is nothing new. I've got two bikes the in garage with this system. I've replaced the bearings in both, and never took the time to ensure that the bearings weren't preloaded. Simply drove the floater in until it stopped and went out and put thousands of miles on the bikes.

I know I'm not the only KLR, Transalp, Vstrom, etc owner who's done this. Why's the Beemer any different?

so dear friends,,,what makes these different is that the ones that are giving trouble are the ones where the bore is undersized thereby causing excess longtitudinal pressure...bores that are properly speced,,even when preloaded will allow the bearing to shift slightly to unload the preload,,,,

so when you have too much pressure on the bearing caused by the bore being undersized well then the ability of the bearing to move laterally gets impaired and won't release unless you take the time to do that via the instruction,hints and diagrams we've posted here

by taking the lateral pre-load pressure off ,you are enhancing the bearings life ,,,same goes for having the correct bore,,,it puts just the right amount of vertical/longtitudinal pre-load on the bearing

get it????

woody

Great thread here. Installed new bearings in both front and rear rims following the info here. All bearing dropped right in without only a tiny tap. Heated everything to 100 C and froze the bearings. Bought bearings at a bearing supply house (a 10 pack) and paid less than half for better quality than BMW was hawking. Didn't have "2 flat faced drifts shy of 47mm od circa at least 2 inches long" but mocked something up using some very thick washers I found and some sockets. Everything went smooth as silk but I was a little bummed when I stuck my finger in the rear bearings and they wouldn't turn easily. Woody to the rescue..I slid the axle in from the sprocket side, put the nut on a few turns and used it like a slide hammer and gave it a couple of pretty gentle pulls. Now the bearings are like butter. Thanks everyone! By the way all 5 bearings were toast at 7000km, (I've been getting them very wet...) the rears probably at 6000 since they felt bad when I checked them then. I now have a nice set of rims from Woody and a second set for street. Not sure if the one factory rear hub I still have has any undersized bores but like I said all the bearings dropped in easy peasy and I can't afford to have a second set built at the moment.