F800GS - headstock bearings

ymfb

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At my 6000 mile service I was asked to bring the bike back in to have the headstock bearings replaced under warranty. Is ths a common problem ?
 
At my 6000 mile service I was asked to bring the bike back in to have the headstock bearings replaced under warranty. Is ths a common problem ?

Yes i'm on my third 800GS and the first 2 had the head bearings replaced under warranty
 
Yes, and if you keep using and paying out the arse end for BMW bearings, it will continue to be a problem.
Source your own good quality bearings and install them using far more grease than any Motorrad tech would ever be allowed to use. The result will be many more miles of smooth steering. When you go to remove the lower bearing, be sure to use a suitable punch in the two little holes which the only genius engineer in Spandau provided for you on the area beneath the bearing on the lower yoke. While you are at it, change your fork oil, too!

Be sure to note the following IMPORTANT note:
If you have the bearings serviced by anyone other than yourself, be absolutely sure they have tightened all the bolts on the steering yokes, especially the UPPER CLAMP BOLT. If the upper clamp bolt is not securely torqued, it can work loose and then slide out of position when you are in a corner and the result will be a loss of steering. My first set were done under warranty in Mexico and I had no choice but to let them do it, I foolishly trusted that the clamp bolt was properly fitted and it wasn't. The result was a very close encounter in a corner at 7,000ft elevation with a very steep drop on one side and a speeding mini van hugging the center line on the other.

I didn't like this situation and harshly questioned the maternal lineage and/or origins of the Motorrad technician.
This was done after the large popping sound happened when I released my glutes from the seat of the bike.
 
Mine were noted as not urgently needing replacement at the 6k service and done under warranty at the 12k service. I'd quite like it if they don't need doing again.

Cheers

m
 
18,000 miles and just on set number 3. There are pretty easy to replace as long as you get a decent needle punch to take out the lower taper from the stem.

I tried having the last set torqued to a lower setting than specified by BMW, this seemed to make no difference to longevity.

It's not just a BMW thing, the first set of head bearings on my Honday Transalp bought new in 2006 also became notch by 6000 miles and needed replacing.
 
Replaced my bearings and adjusted correctly. Done 300 odd mile and checked again. Very Slight notch in centre. Skf bearings. When I slacken them slightly the notch goes away and it's perfect. Is this normal? The notch was very minimal.
 
Yes, and if you keep using and paying out the arse end for BMW bearings, it will continue to be a problem.

BMW don't have the bearings made for them, they use propriety NSK'S SKF'S etc. Plus you can put as much grease in there as you want. The taper bearings are rollers and will 'wipe out' any excess grease, leaving a very thin film between the roller and the surface of the bearing :nenau

The grease must be waterproof. I've done 88,000 miles now and had six sets in :eek:

Adjusted to the letter of the manual, a little tighter, a little slacker, lots of grease, adjusted 'trial and error' .... still cheaper than a 1200's final drive :D

Doesn't even bother me, no whinging, I'm totally happy with the bike and just consider the head bearings a virtual replacement at service. No big deal, forty quid now and again and two or three hours work.

I reckon it's down to the steering geometry. The Triumph 800XC is almost identical and they're having problems I'm given to understand. Also the quality of the bearings, even the top brands. The taper bearings are designed to be spinning, not taking the load like they have to do.

Just one, maybe two, depending on position within the race, at the top and bottom, taking all the strain ... they only move position and contact when the bars are turned, when the bars are back in the straight ahead position (where all accelerating and braking forces take pace) the roller bearing take up their former position ....

..... but then what do I know :rob

:beerjug:
 
Very true Micky. Final drives just a tad more expensive to be replacing. Have u came across this with leaving bearings slightly slack to remove a notch be it only very minimal. Bearings are new 300 miles ago.
 
Very true Micky. Final drives just a tad more expensive to be replacing. Have u came across this with leaving bearings slightly slack to remove a notch be it only very minimal. Bearings are new 300 miles ago.

I've come to the conclusion that the old belief that there should be a teeny weeny bit of play in a taper bearing for such as wheel bearings .... where it's spinning, and a little too much preload on such a bearing is fatal ... is true!

BUT any free play in a steering head bearing will knock the feck out of itself all too soon :blast

Years ago when the K100RT's were having a right problem Bedfordshire Police locked their chief mechanic and top instructor away to look for the probs.

They found that, amongst several other things, the head bearings were very very critical in their adjustment, as to what speed the instability came in. Here in South Yorkshire we followed their modifications and I was tasked to road test the bike's after the modifications :rob

Health and safety wouldn't allow it these days of course, and all tests were conducted on a private aerodrome runway :rolleyes:

The matter of a 1/4" (not a quarter turn, and this is before metric) of adjustment on the head bearing adjuster would raise or lower the speed that the wobbles would set in, or eliminate them altogether :eek:

A fat rider never had a problem ... but I was young and slim in those days :D

:beerjug:

Edit .... yes, when you feel they are notched then backing off a tad will eliminate for a while, but you're only postponing the inevitable!
 
:stupid , but 27,700 Miles

tightened two weeks ago made a huge difference in feel :thumb2 :D

(no offence meant)

I agree :thumb

I think they settle down and become a little slack, not so as you'd notice, until you adjust them up a bit and take that slackness out .... and before they knock themselves to bits.

:beerjug:
 
There was no slack back and forth just very minimal notch. Hope the slight slacken off is it sorted now. First set lasted 12 thou.
 
Any body know the correct adjustment procedure for tightening the big centre nut. Cheers. :thumb2
 
Mine were noted as not urgently needing replacement at the 6k service and done under warranty at the 12k service. I'd quite like it if they don't need doing again.

But at the 18k service they decided that this set also need replacement - also under warranty. 6k from a set of headstock bearings! Shocking.

m

posting here instead of going out and riding my f800gs
 


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