► Steering head Bearings

[sijohnston]

In the middle of doing my head bearings and done the stripping and removing. It's a real pain in the arse. After messing around with a chisel to try and get the bottom bearing off, I threw the front wheel/forks around to an engineering firm who ground it off for £15. Now got the new races in place and about to put all back together. Hope I get the torque settings right!

The removed bearings seemed not so bad, given what they've been through, so really hoping this mends the twitchy low speed steering issues. Trying to get it done while at work so that I can make it to the NW200 tomorrow after work.

 

[MikeMike]

Why didn't you just use a good punch or a concrete nail in the conveniently provided hole (one of two) that is found on the bottom of the steering head precisely for the purpose of removing the lower bearing?
On second thought, why didn't the engineering firm do this? Oh, well...
Take a look at these threads.

http://f800riders.org/forum/showthr...ering-head-bearings/page2?highlight=EmmBeeDee

http://f800riders.org/forum/showthread.php/82382-Third-steering-head-bearing-is-toast


The first thread, on the second page, has a very clear photo of the two holes.

 

[Jonnie Boy]

Do 'Quality' bearings last longer?? whats your experience?

Had my head bearings done under warranty at 12,000 miles, they now need doing again at 30,000 miles! Out of warrenty . Therefore requiring an unearthly sum of monies to fit by the dealers!!

A couple of questions to those who fitted your own...

Which make to fit?

How shitty/corroded were the old ones? Is it worth fitting sealed type ie 320/28JRRS NTN SEALED?

How have 'quality' bearings, fitted and greased properly, held up compered to a BMW fitment?

Fitting new bearings myself will be a bit of a fuss in my tiny shed so would like to get this done right so as not to have to repeat every feckin 18,000miles mumble grumble.......

Would appreciate any observations

 

[Smythson]

I did my own however it wasn't that long ago - factory ones died at about 12k and only done a further 6k on new ones so i can't really help with estimates of longevity.

I'm not a mechanic so it take me a couple of hours. On the offchance you don't notice (like i didn't ) there sre two little holes in the bottom triple that allow you to feed a blunt nail through to knock the bottom bearing up.

This may help -

http://advrider.com/forums/showthread.php?t=716362

With regard to brand - i like knowing that what i've done will last so went for the SKF option. According to the specs offered by simply bearings thay are actually stronger so will hopefully last longer than the outgoing NTNs that were factory fitted.

Happy wrenching,

S

 

[Jonnie Boy]

I did my own however it wasn't that long ago - factory ones died at about 12k and only done a further 6k on new ones so i can't really help with estimates of longevity.

I'm not a mechanic so it take me a couple of hours. On the offchance you don't notice (like i didn't ) there sre two little holes in the bottom triple that allow you to feed a blunt nail through to knock the bottom bearing up.

This may help -

http://advrider.com/forums/showthread.php?t=716362

With regard to brand - i like knowing that what i've done will last so went for the SKF option. According to the specs offered by simply bearings thay are actually stronger so will hopefully last longer than the outgoing NTNs that were factory fitted.

Happy wrenching,

S

Thanks for the reply.

Yep had a look at the Advr thread and there's a similar on F800riders, I think it was. So was aware of the yoke holes for the removal of the lower stem bearing.

NTN are reputed to be a reasonable brand so it does seem odd that these failiures occur with such regularity.

I probably will therefore follow your lead and fit SK's and see what happens.

Appart from 'notched' what state were your bearings in, on removal? any signs of water ingress?

 

[illumeo]

The Dealer is replacing mine, under warranty, will let you know what state the old ones are in once the job is done. Slight notch at the moment. After reading this thread, will be supplying some SKF's for the job.

 

[Smythson]

To be honest i wouldn't know specifically what water ingress would look like. From what i can make out there was a very fine paste made of dirt and not much in the way of grease left and the notches were even all the way round. I think it's the general opinion not enough grease is used in the factory so the replacements were caked to make sure.

Hope helps,

S

 

[RickM]

I know this is a bit of an old thread but I've only recently bought my first BMW (800GS) after 25 years of Japanese trail bikes. I needed something to replace my 130,000 mile '09 Tenere for courier use and wanted something with more power but equal/better fuel consumption - the 800cc Rotax seemed a peach.
I bought the bike with a little over 16,000 miles on it and when I took it in a few weeks later for the 18,000 mile service it needed the steering bearings replaced which they duly did free of charge. Fair do's, I thought. But they then said that they had replaced them when they bought the bike only 2000 miles earlier! At just over 21,000 miles, the steering was notchy again so I replaced them myself at the weekend. The bearings I removed were NTN - a brand I have used many times over the years without issue.
Could the problem lie in the fact that the bearings aren't big enough? Not trying to be controversial - just an innocent question based on observation. In the attached picture you can see that the 800GS lower bearing (the one that takes the most abuse) is smaller than the one from the XT660. Further the 800GS bearing has 19 rollers (points of contact that spread the load) whereas the XT has 21. They are similar weight Bikes with the XT having significantly less power.
Just an observation....

 

[Bendy toy]

Taper rollers are better then the older style loose ball bearing head races. But to be honest rolling element bearings of any type are the wrong system to use for a nearly static or oscillating joint. At least bike steering is periodically swung over larger angles at low speeds to spread the grease about.

Rolling element bearings are designed to recycle the rollers to spread the loads over the whole roller surface. When its static the same bit of every roller and the same bit on the races gets all the load and grease gets squeezed out so its no wonder they get notched. Also make sure they are not overtightened. Enough to have no slack is all they need on a head race. Check regularly and retighten as they bed in.

This bearing type needs no grease and gets used in agricultural equipment so its tough. They might even have sizes to fit but for sure spacers would be needed. http://www.igus.co.uk/wpck/default.aspx?pagename=igubal_sphaerische_Axiallager

 

[MikeMike]

Could the problem lie in the fact that the bearings aren't big enough?

Absolutely.
Couple that with the fact that BMW charges about 600% per bearing in parts price mark up and you've got a nice little money maker where they can fleece those who don't go the DIY with their own sourced bearings and seals. I replaced my wheel bearings front and rear and my steering bearings with all new seals and packed chock full of good quality grease, for a little more than the cost of one single bearing from the BMW parts counter.

 

[RickM]

Hmm...interesting Bendy toy. What other type of bearing would you suggest? Taper roller bearings have been fine for years in other bikes I have owned.

Sure thing MikeMike, I was prepared for some increase in parts/labour costs but wasn't expecting a standard mass produced component to be wearing out so prematurely. I guess I'll have to invest in a torx socket set and maybe a steering bearing puller - although my "universal" tool for removing the lower bearing off the stem (made by Dremel!! ) has worked so far .

Oh well, the way I look at it; I've bought a brilliant Rotax engine with some BMW parts attached!!

Hopefully the great mpg will balance out any negative BMW "character".

 

[RickM]

So after approx 3000 miles they need changing again!!
I'm thinking the front end may be too stiff?? When I change the bearings again I'm gonna try lighter fork oil and less air in the front tyre........

 

[rodooo]

Changing or just maybe need tightening up. Use good quality waterproof grease and should have no trouble for years

 

[Jonnie Boy]

Jus done mine 3000miles ago, now need redoing! Used wrong grease, water got in and now all corrroded. Doh! Gonna be trying sealed bearings and pukka Castrol EP2 grease.

 

[RickM]

Unlucky John.
In my case whilst any grease will provide lubrication and prevent corrosion, it did not provide my steering bearings with any shock absorbing properties as seems to be implied on several occasions.

I think it can be safely surmised that the bearings are taking more force than they can handle for long term survivability (mileage not time).

BTW, 3,000 miles is less than a months worth of riding for me so I don't think the amount/type of grease will make any difference.

Just out of interest, it would useful to know what front tyre pressures people are running (and whether front suspension is standard or not) vs how long the steering bearings are lasting.......

 

[rodooo]

Mate on his second 800 and never put bearings in any. Both with 30 thou plus miles
All standard bikes and tyre pressures as per manual

 

[RickM]

Yeah, just like my Tenere which at over 130,000 miles still has the original clutch and front discs (which are rock solid and don't rattle on their bobbins).
So I must just be used to riding Japanese bikes in a way the 800GS can't handle.

 

[MikeMike]

Those Teneres have the right sized bearings, they are very stout compared to the smaller BMW steering head bearings, do a side by side comparo and you'll see how Yamaha got it right.
I don't think the BMW issue is related to tire pressures nor forks, the issue has come up on the F650GS and the F800GS. I am convinced it is a combination of a low quality, undersized bearing, installed at the factory with the least amount of grease possible. This means owners can choose to change them themselves and save a huge amount of money or take it to a dealer and pay out the arse for the same shoddy bearings and lack of grease as from the factory.
If you do it yourself, remember the two little holes conveniently found on the underside of the lower yoke of the triple tree, those are there for you to insert a correct punch and take out the old lower bearing and the dust shield will be sacrificed so you'll need to source one of those.

 

[Steptoe]

The older F650 was renowned for a short steeringhead bearing life due to the engine oil in the frame.
The heat used to dry out the bearings.

 

[RickM]

Ironically Steptoe, there was a similar odd occurrence of that with a few of the Tenere's (insufficient grease during factory assembly).
Yep MikeMike, insufficient bearing size was my first assumption but I have been led to believe that there are plenty of bikes (eg R1) with similar size bearings with no issue.
My suggestions re tyre pressure and front suspension are merely a "band-aid" fix more than anything else....