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Discussion Starter #1
Got the forks off (not with a little tapping and wiggling) and they are ready for the rebuild.

However, I noticed what feels like a little detent in the steering head at the center. I don't think this should be there. Is anybody aware of a notch or detent at center? It's hard to tell but it seems to "pop" into center as it gets close. happens from either direction.

I'm thinking there is "while I'm in there" project of also changing out the steering bearings. They are after all, 25 years old.
 

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There is no detent, make sure the cables or hoses are not binding.

Bearings are most like hammered and now is the best time to examine them even if you did not detect the detent - they need lube.
 

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Sounds like the steering head bearings need replacing to me. They usually tend to get a lot of force applied to them with the bike pointing straight ahead, so the bearings get hammered in that position and lose a bit of material. The symptoms you're describing about feeling like a detent are classic symptoms.
 

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one issue with the way the ss were done ex factory was that the bearing adjustment was set, then that top nut was tightened like all fuck, preloading everything way more then it should be and giving the bearings an extra reason to get notchy.

if you had one with the front up and loosened the top triple pinch bolts on forks and stem then undid the top nut the reduction in bearing preload was quite astounding. we used to do it at first serivce, and then just leave that top nut nipped up. once the clamp screws are tight the nut is a bit redundant.
 

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Discussion Starter #6
ya....posted over on the 900SS FB page as well and the clear consensus is the bearings are toast. I'll get in there while the forks are rebuilt (which are also way over due).

Thanks for all the input.
 

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Mine were totally destroyed right on center and I could barely feel it, so if you can feel it, it’s got to be bad. AllBalls has a nice replacement set.
 
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Right before I totalled my 899, I noticed the same thing. Well, not RIGHT before, but maybe 5,000 miles before. I only noticed it while I had the front end off the ground and had asked around to confirm my suspicions! I had almost 83,000 miles on mine so I guess it was time.
 

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Discussion Starter #9
Mine were totally destroyed right on center and I could barely feel it, so if you can feel it, it’s got to be bad. AllBalls has a nice replacement set.
Found the set on AllBalls. Thanks.
 

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FWIW

For what ever it's worth, the steering head bearings are the same as the wheel bearings on 1954-1962 Fiat 500s. If you search for them using that information you'll find them available all over the place for little money. I used 1957 as my model year and found them on Rock Auto for about $30 delivered to my door. That's for both top and bottom sets...arrived in just 2 days also....sean
 

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That’s about what the AllBalls bearings cost.
 

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Good info on the bearings. oem are about $55. per set so times 2 = $110 ish from Ducati. They are a good quality bearing but... The Chinese allballs have worked good enough for most though I doubt they are equal quality. In the end if they get you near the same life who cares where they are made.

I will have to order up a set of the National and centric bearings to give them a try.
 

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The aftermarket tapered rollers are a huge improvement. Like night-and-day difference in cornering on my ST2.
 

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If possible I would put caged ball bearings in all of my bikes steering heads, comparing worn out anything to new is not a fair comparison. I see many more sets of tapered roller bearings need to be changed than caged ball and there is noticeably less drag with the balls. I think the size of the ball bearings are why we do not see a proper caged ball setup for our small neck application.
 

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Good info on the bearings. oem are about $55. per set so times 2 = $110 ish from Ducati. They are a good quality bearing but... The Chinese allballs have worked good enough for most though I doubt they are equal quality. In the end if they get you near the same life who cares where they are made.

I will have to order up a set of the National and centric bearings to give them a try.
Nothing against Chinese made bearings. I've used them in all manner of applications and never once had a manufacturing related failure.

Some of the bearing sold by/as quality named products are in fact made in China. I've found this to be true with National, CRC, Bower and several others including SKF. Proper name on the bearing with Made In China opposite.

As the OEM bearings are SKF, it's a crap shoot where the replacements are made should you order the SKF name brand. Some are made in Italy. Some are made in Spain. Some are made in China.

When I ordered the multitude of bearings required for my 900 SS project, I got some of each. Not because I chose them that way, that's just what came out of the boxes when I opened them.

In the end, I don't much care save for my wheel bearings. Those I cross referenced the SKF number to Timken. I received bearings made in the US but with a higher speed rating than the OEM SKF bearings.

On the SKF web site, the OEM bearings were rated at just 10K rpm. The Timken bearings are rated at 20K rpm. I don't know what rpm the wheels are turning but I figure the higher rating equals a higher quality bearing...sean
 

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i think the balls are ok for aluminium frame bikes, where they seem to last for a long time. in the aprilia's even with 40nm of torque on them, they last well. and in the 916 and mv with the aluminium insert in the steering head they last well. we used to drop the torque back to 10nm at first service and they were good like that. most of the mv ones i replace are due to rust.

but in a steel frame i think they're a crap idea. we started replacing st2 ones at 10,000km services, same for the cheap 748 without insert and the st4/4s. i can even recall dropping a 748 lower triple out and having a cup of water come with it.

i think the ball bearing load area is just too small for the impact loading that is not able to be absorbed anywhere else. when they're really notchy there's only tiny dot marks as wear, but you can feel it clearly.

i only ever fit tapered rollers to replace them, and they last so long (those big ones have so many rollers, more than the smaller 069191010) that there's no point using the balls imo.
 

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Nothing against Chinese made bearings. I've used them in all manner of applications and never once had a manufacturing related failure.

Some of the bearing sold by/as quality named products are in fact made in China. I've found this to be true with National, CRC, Bower and several others including SKF. Proper name on the bearing with Made In China opposite.
There's a lot of misunderstanding about OEM. As @Iwannaduc states, just because it says OEM, doesn't mean it's been made by Ducati, SKF or whoever.
 

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Different experiences are common and it is all good to add to the data.

We have changed tapered rollers easily 3 to 1 over caged balls. It is very rare to have superbikes need them but that may be more to the fact most superbikes do NOT see high miles. I still replace more tapered rollers in supersports (tepered rollers) than monsters and sport classics ( with caged balls) probably 2-1. Over 20 years of working on these bikes full time with both I think the problem with the balls is the size of the ball.


Back in the old days of uncaged balls the balls were very small and steering heads did not allow larger balls to carry the load, this is a place where you would expect the tapered rollers greater surface area to be a benefit. The aluminum insets gave the bearings the size to have a physically larger bearing carry the load This may have been one of the reasons the steering heads were increased to use the larger bearing instead of continuing with the smaller (and cheaper) bearing. I install both these days mostly as a cost constraint as the caged balls are more pricey and tapered rollers plentiful at many price points. I do not see Ducati choosing to design in inferior bearings that cost them more to buy so there is that as well.

Now do not take it that I am anti-tapered rollers as they certainly do have their place and if you prefer to remove bad bearings and install new bearings you will sing their praises as well. Much like carburetors there is some comfort in old tech and there is nothing wrong with it, I simply see it as picking which option suits you best and understanding why.

I agree whole heartedly on the Chinese bearings being acceptable ... as long as they are backed up with a known company backing up the quality control. A SKF,Timkin etc bearing made in most anywhere is fine with me as long as someone in the company is keeping an eye on quality and consistency. If you are buying instead a bearing made by a brand (or no brand) that you do NOT know you are simply buying an unknown. They may prove to be as good as the known brand, maybe even better! But without having the full weight of a company who does NOT want to risk a hard earned reputation I often see little to be gained by saving a few dollars to be part of the experiment. But someone will and we can then build a track record with these new companies to decide again next time where to place our trust and money.
 

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just had a quick look. the 069191010 tapered roller from the ss, etc, has 16 rollers, the oem 916 onward ball style have 18 balls and the tapered roller replacement for the ball style has 24 rollers.

we used to do lots of ss and pre 02 monsters at 20,000km. probably all of them really.
 

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Moisture is the biggest problem with head bearings . I use boat trailer wheel bearing grease . I stick with name brand bearings, but I don’t buy direct from China because they are famous for counterfeit products. I buy from eBay or a bearing company because they get their stuff from a known source. If you buy from eBay many times they have pictures of the actual bearings and boxes so you can verify yourself what you’re buying. I usually can get brand name bearings for a good price there, many times no more than the “ cheapos “ cost.
 
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