Headstock Bearings

[tonythecat]

I am looking at the taper bearing conversion as supplied by Christian Patzke, has anyone fitted these? if so what are they like to fit, any machining required?,and what are the overall impressions?
Thanks

Tony

 

[john998]

Head stock bearings

Hello,
someone out there must have an insight on this subject.
I would like some information too.
John.

 

[John Cone]

There was an article in MPH sometime back, perhaps in Robert Watson's time as editor on the fitting of tapered headstock bearings.

 

[Tracey Tilley]

Our Rapide has them fitted.

I'll get Chris to give me the info.

 

[Tnecniv Edipar]

Pretty sure there will be something in FYO.

 

[petermb998]

When you get a set from Christian Patzke you will find full instructions supplied with the kit.

I fitted a set in 1998 with no problems.
The only bit of machining/mod that I did was to grind 2 notches at the bottom of the bearing housing in the head stock.
Just enough to enable a thin drift to knock out the outer bearing
This will make it easier to get the outer bearing out at a future date if required.

Also if you can get some use a water proof grease for the bearings.
Fit and forget.
Good luck with it.

regards Peter Bromberg

 

[tonythecat]

Pretty sure there will be something in FYO.

Can't see anything in FYO, but in ATY, page 23 there is a sales pitch from the producer of the kit, but really tells very little about the fitting, or obviously and independent appraisal.
Thanks.
Tony

 

[vince998]

Can't see anything in FYO, but in ATY, page 23 there is a sales pitch from the producer of the kit, but really tells very little about the fitting, or obviously and independent appraisal.
Thanks.
Tony

I fitted a set three or four years ago to my D shadow, and to a mates egli.
The fitting is very simple. Don´t forget to check that the nose of the bearing inner doesn´t catch on the lip of the headstock inner bearing seat. Should this be the case, a dremel and 10 minutes to taper the lip down is all you need. (top & bottom)
Initial bearing adjustment can be a bit tricky depending on how indented the steering stem is from the top clip pinch bolt (on tightening, the whole assembly wants to adjust itself back to where its been for the last 50 years)(please don´t ask me for part numbers, it´s been a while since i looked in the catalogue).
Wear is non existent,and were it not for the yearly greasing ritual, i wouldn´t have to touch it.
As i mentioned, very simple to fit,very friendly in maintenance, but a bit on the pricy side (Christian has to disasemble the bearings, and get the cages ground down to fit our head lugs, then reassemble)
If i´d had access to a decent lathe, i´d probably of machined the bearing seats out to take standard timkins.

Hope this helps tony.

 

[roy the mechanic]

taper bearings

Firstly, the guys at Stevenage may well have been "lunatics", by the same token they were not fools. The rollers in taper bearings are larger in diameter than the cup+cones of the originals. This means that the movement of the tapers is less than the balls, consequently the wear pattern will be over a smaller area. When your "new fangled" bearings have done the same ammount of work as the originals(if you ever cover the same mileage!) They will not respond to a small adjustment as the tracks will be indented. Your steering will feel life a threepeny-bit(if you remember such things). Not all "improvements" are for the better. Be forewarned. Roy.

 

[John Cone]

I couldn't agree more with your comments Roy. I changed from ball bearing to taper roller on my old trusty CX500 many years ago. One time i thought i would give the headstock a bit of attention and repacked the bearings with grease, after reassembly i went up the road and at the first corner the bike almost threw me off. it was like a ratchet when you turned the handlebars. Ball bearing will eventually rotate their way all the way around the cups they site in provided they are not packed to tight. The ball races on my Prince looked as good as new when i came to puting the front end back together a couple of months back.

 

[vince998]

Firstly, the guys at Stevenage may well have been "lunatics", by the same token they were not fools. The rollers in taper bearings are larger in diameter than the cup+cones of the originals. This means that the movement of the tapers is less than the balls, consequently the wear pattern will be over a smaller area. When your "new fangled" bearings have done the same ammount of work as the originals(if you ever cover the same mileage!) They will not respond to a small adjustment as the tracks will be indented. Your steering will feel life a threepeny-bit(if you remember such things). Not all "improvements" are for the better. Be forewarned. Roy.

Whats the point in taper rollers in the swing arm then?
The movement in the swing arm(sorry, RFM) is much less than the head bearings, or have i missed something here?

Probably something to do with surface area? (every bike after 1975 i know uses taper rollers for steering)

Ref improvements: hammer the standard bearings (accident or big pot hole), you´ve more than likely got micro dents in the race!!!. With rollers, you´ll bend the forks firstt

 

[vince998]

I couldn't agree more with your comments Roy. I changed from ball bearing to taper roller on my old trusty CX500 many years ago. One time i thought i would give the headstock a bit of attention and repacked the bearings with grease, after reassembly i went up the road and at the first corner the bike almost threw me off. it was like a ratchet when you turned the handlebars. Ball bearing will eventually rotate their way all the way around the cups they site in provided they are not packed to tight. The ball races on my Prince looked as good as new when i came to puting the front end back together a couple of months back.

John, due to the larger surface area of roller bearings, any mistake in adjustment (in this case, over adjustment,!!) is exagerated. Take a bit more care & don´t blame the bearings.Commen sense prevails !!!

 

[Tnecniv Edipar]

The RFM is subject to virtually only radial load , the headstock has radial & axial load. However , in practice a TRB will easily handle the forces involved in the headstock , otherwise , as has been said above they would not be used in almost all motorcycle headstocks since a long time ago. The biggest killer of headstock bearings is incorrect adjustment and corrosion from standing for long periods in one position. Tip for maintenance , use waterproof grease for lubrication , standard LHM grease will allow moisture to penetrate over time.

 

[vince998]

The RFM is subject to virtually only radial load , the headstock has radial & axial load. However , in practice a TRB will easily handle the forces involved in the headstock , otherwise , as has been said above they would not be used in almost all motorcycle headstocks since a long time ago. The biggest killer of headstock bearings is incorrect adjustment and corrosion from standing for long periods in one position. Tip for maintenance , use waterproof grease for lubrication , standard LHM grease will allow moisture to penetrate over time.

Waterprooof grease overcomes the problem of standard greases in the respect that they are not/ not so hydroscopic (water absorbant), but this will not overcome the problem of water ingress, rather exgaterate the problem in such that once water is in, it cannot escape. i´ve had similar problems with waterproof plugs/connectors. Once in,(through ingress or condensation, doesn´t matter) it can´t escape!!!!.

 

[Prosper Keating]

Even if TRBs in this application had half the average life of BBs, they're probably superior in many respects on the road. Of course, many members' machines no longer do much road work so corrosion during long periods of disuse may well be a problem.

Vince raises a good point about waterproof greases. Regarding grease in general, it is a good idea to disassemble components lubricated with any kind of grease from time to time, clean them thoroughly and regrease them. It is also a good idea to use grease nipples for their intended purpose.

BMW has used TRBs since the early 1950s. My Series 2 had TRBs in the steering head and both swinging forks. They are a better bet than BBs as the Earles forks are heavy and the same must logically apply to Girdraulics. I have BBs supporting my Girdraulics and they are trouble-free because I check them at least once a week, given the cobblestones and other vagaries of Parisian streets.

I might well fit TRBs when the time comes for a change. It is true that adjustment is a precise art. As a general rule, it is a good plan to remove all control cables from the equation and to jack up the front end so that you can feel the movement from side to side. Those of you used to BBs will see this as a royal pain in the arse in terms of weekly maintenance. However, this is offset by the fact that your TRBs, once adjusted properly and locked off, may need no further attention for months or even years. In other words, at regreasing intervals.

I probably wouldn't bother with TRBs, on the other hand, for my Bramptons as the BBs seem perfectly adequate for the job, even though Bramptons seem to be heavier than Girdraulics. Unsprung weight may be greater though as the low speed steering is certainly as ponderous as that of an Earles-forked Series 2 BMW, whose unsprung weight is rather more than that of the average telescopic fork.

Regular use and regular maintenance... Can't beat it for keeping old machines happy and in good order.

PK