Head Bearingings

[bobajob]

I've stripped my '76 Strada down to the frame for a repaint and am trying to decide the best plan of action for the head bearings.

I've removed the cups from the frame and the external surface is badly corroded. Obvious option is to fit taper roller bearings, anyone have any experience / views on this? Is it just a case of going to a bearing supplier with in ID and OD measurements? I've never done this conversion before and from what I can see you will lose a few mm's from the length of the headstock as the original bearing cups have a shoulder. Also do you need to fit any type of dust cover or seal?

Any advice greatly received!

[EVguru]

Personally, I'm not a fan of taper roller head bearings. They're very sensitive to adjustment and to the headstock being in perfect alignment. Quite a lot of modern sports bikes have gone back to cup and cone!

If they're otherwise in good condition and it's just the look of the chrome that concerns you, why not rub them down and paint the outside. Chrome can be applied selectively by a competant plater, so you should also be able to have the outside re-chromed.

If you really want to go to taper rollers and you don't have the capability to make your own, then Wolfgang Tritsch has a kit; http://www.w-tritsch.de/html/body_morin ... teile.html

['It must be a .....']

If you can get a pair of 'cups' for the taper roller bearings from a later Camel, Kanguru etc, they will fit straight into 350/500 road bike head stock: the bearings are a standard size and new ones are easily available from a bearing supplier.

[bobajob]

Thanks for the replies, all good stuff. I'm going to start by seeing if I can get the cups plated. I like the idea of keeping the original setup, it worked well before i stripped the bike. The only issue is the state of the chrome.

I swinging arm bearings on the link look interesting.

[EVguru]

swinging arm bearings on the link look interesting.

Wouldn't touch them with a barge pole!

The bores in the swing arm don't line up well enough and the bearing area is rather limited. The spindle also isn't really hard enough to run the rollers directly on it, I've seen the Brinelling to prove it. The Original bushes are cast Iron on Steel, which is a reasonable bearing combination, but the straight lubrication grooves are far from ideal. My bike runs Bronze bushes, line reamed in-situ, but since then I've done two conversions to PTFE bushes on stainless Steel. Martin Gelder has the first and it seems to be holding up well.

[pedro]

I recently had the same problem with rusty cups, Rob at NLM had 14 secondhand ones and he sorted me out one with as new chrome at a cheaper price than re-chroming would have been, always supposing I could have found a plater able to chrome just the top part. You really don't want chrome on the bearing area. The top cup is mostly covered with the bearing cover so I used the best one on that and just replaced the bottom one.
Pete

[bobajob]

Thanks Pedro, I'll give NLM a call! I did speak to them last week but I asked the wrong question. They do a taper roller conversion for £120 + vat, this is a lot to spend just to resolve a cosmetic problem and I would prefer to stay with the original setup.

[buzby]

Some help please. I have just stripped my 76 sport down for powder coating the frame and was surprised to find 21 ball bearings at the top and 22 at the bottom.I presume it should be 22 for both but I can not find evidence for this.

[bobajob]

Yes I'm sure mine had 22 top and bottom.

I know this as I dropped them on the shed floor, and spent ages making sure I had found them all.

[chirpy999]

There might not be a problem with different numbers of balls between the top and bottom. I am doing a Gpz 550 restoration and that has a different number between the top and bottom cups.

[Michael S]

Hi Every one
Preparing my '82 Strada for an overdue MoT and noticed a slight slack for and aft on the head stock.
Steering is nice and smooth.
Can I make a very slight tightening of the bearing?
I have not got a diagram of the head stock. Is it just a matter of slackening the pinch bolt and turning the large hex in the centre top of the fork assembly?
Regards
Michael



























steering ius good with

[Steve Brown]

Wow that's an old post you've dug up! Yes, you should be able to take up the play and the adjustment is as you've guessed. Obviously don't go too hard on the adjustment, merely gradually take up the slack and check it as you go, a little at a time. If there is no 'notchiness' after the play has gone you're fine.

[Steve Brown]

Wow that's an old post you've dug up! Yes, you should be able to take up the play and the adjustment is as you've guessed. Obviously don't go too hard on the adjustment, merely gradually take up the slack and check it as you go, a little at a time. If there is no 'notchiness' after the play has gone you're fine.

Oh and it's worth slackening the pinch bolts holding the stanchions into the top yoke too!

[Michael S]

Many thanks chaps. I do love Forums and tha people who support them
Keep up the good work
Michael

[norbert]

Personally, I'm not a fan of taper roller head bearings. They're very sensitive to adjustment and to the headstock being in perfect alignment. Quite a lot of modern sports bikes have gone back to cup and cone!

If they're otherwise in good condition and it's just the look of the chrome that concerns you, why not rub them down and paint the outside. Chrome can be applied selectively by a competant plater, so you should also be able to have the outside re-chromed.

If you really want to go to taper rollers and you don't have the capability to make your own, then Wolfgang Tritsch has a kit; http://www.w-tritsch.de/html/body_morin ... teile.html

I totaly agree with Paul! If we do have a weak point with the chasis these are the swing arm bearigs (or better said the poor quality of the shaft).
Apart from the required pefect alignment, that is not garantied on our bikes, the center tube of the fork becomes too short. I´ve bought the base of my actual 500 Frankenstein project 15 years ago. The former owner has had a low speed accident turning on the street with a gripped taper roller head bearing. When I dismantled the bike I´ve found out, that the central screw only was involved about 2 turns in the center tube of the fork!
Of cause you can unse a larger screw but its not a perfect fit in the upper yoke. These bearings maybe a choise if all is perfectly aligned and then they are easier to change. But I´m convinced that tecnicaly they arer not superior to our original bearings.