Clutch Hub Needle Bearing

Was swapping out clutch steels and fibres, when I noticed that the clutch hub needle bearing is noisy. Have never seen an exposed needle bearing before. Is the noise normal or if not, where on earth to get a new one.

 

you dont mention which bike you have, not all xj's have clutch hub needle rollers, unless you are talking about the clutch arm throw out bearing,

 

Sorry about that. 1981 XJ750 RH.

 

If your talking about this then they normally dont go bad but if in doubt replace it. Check the riding surface on the pusher and the plate for wear.

https://www.partzilla.com/product/yamaha/93340-21505-00?ref=7314e60dd4b8a1911233993a174ac915181a029c

 

Cheers Wayne for that.

 

Have you got any side to side movement of the clutch hub? Is part 33 worn? Worth checking while you are in there and you should use new bolts.

https://images.cmsnl.com/img/partslists/yamaha-xj750-maxim-1983-d-usa-clutch_bigyau0852c-5a8d.gif


Clutch grenade photo

https://xjbikes.com/forums/threads/clutch-issues-after-rebuild.130158/#post-660887

 

we still havent established if his problem is with part 3 or part 33, of the diagram Franz posted <
i.e. clutch throw out arm bearing ,or clutch hub bearing.

 

Since he stated that he has never seen an exposed needle bearing before I assumed he was talking about the throwout bearing as he was removing the plates, you cannot see or view the hub bearing unless you disassemble the clutch. Most people wouldn't even know bearing 33 was there. Unless the bike has been badly abused you should have little problem with either of those. But always good to check.

 

My machine had an intermittent screeching noise and it was the clutch hub bearing. It also had play in the clutch hub.

 

Ya always good to check, he would have to pull the clutch hub to replace or inspect. He didn't mention anything about pulling the hub. I guess we will need to wait and see if he can give us more info.

 

Mine sounded like this Suzuki.

 

O ya I would be tearing into that. I would automatically think it's the hub bearing. Now if you only hear it when you pull in the clutch then the throwout bearing. Either way way does not sound good.

 

This is the thread on my bearing Wayne l posted a video on. At first l thought it was the small throw out bearing on mine.

https://xjbikes.com/forums/threads/rattling-noise-on-start-up-yamaha-xj-900f.119637/

 

Franz, looking at your post and video that bearing is toast. Then I started to look closely at something I thought was a bit strange. I normally work on Kawasaki Z1900's and have not taken many Yamahas apart. To date I have worked on 72 XS650, 73 RD350, and the 82 XJ550. Cant remember too much about them. Earlier I stated those bearings normally don"t fail. Well at least on my Z1 bikes. So take a look at the Z1 hub bearing compared to the Yamaha bearing for the XJ750 and your XJ900 I believe and tell me if you notice any difference that may contribute to that failure.
My z1 bearing

and the XJ750 bearing I found on eBay
https://www.ebay.com/itm/2757101247...MI8c_1mY6Z_gIVaxKtBh3ZqgS6EAQYASABEgL8TfD_BwE

 

The Z1 bearing flange which looks like it's part of the cage is the obvious difference. My 900 bearing is less robust looking. I am no engineer but looks to me like the Z1 bearing would not oscillate if that's what's happening with the worn Yamaha ones.


Just looked at the exploded view. But the Kawasaki one looks heavier.

https://images.cmsnl.com/img/partslists/kawasaki-z1b-1975-usa-canada-clutch_bigkar119661213_a0d2.gif

 

That is true but it's still a cage needle bearing as is the Yamaha bearing. That bearing will come off that flange. The main difference is the number of bearings on the z1900. It has over twice the amount of bearings which gives it a much greater surface area. Look at the spacing on the Yamaha bearing and you can imagine how much force that those few rollers need to take per bearing

 

Yes that is right l hadn't thought of that. Now l am thinking is there a suitable bearing with a lot more rollers than the standard Yamaha one that would fit the XJs?

 

I would say yes. You would need to get the measurements of the two surfaces that the bearing rides on and the thickness of course. How many miles were on that failed bearing on your bike.

 

34,000 miles on it when l got it. Bearing didn't last long after that which surprised me as l thought they would last longer. The engine is in great condition l fitted a new alternator/ starter clutch plastic guide last year and a few other parts when l had the cases split.

 

Some bearings have clearances l believe like C3 etc.

 

It would be interesting to research that bearing a little. It's kinda a weird design if if you ask me. Im assuming cost would be a factor for that bearing. That design is used on the 650 on up. My 550 is not like that

 

Yes l think so too. I am going to check if Yamaha used it in other machines. I know they used on the 900s Diversion. @chacal will know l think. He might chime in. Why did Yamaha use fewer rollers than other manufacturers?

 

I believe it was used in the 600,650,750,900 machines maybe others. It would be an interesting project and also see a few other opinions on that bearing. To me it seems that they could have used one with twice as many rollers. I cant see any benefit of having fewer rollers other than cost but i'm not a mechanical engineer.

 

Yes l agree. Yamaha used that bearing on 152 models according to Consolidated Motor Spares in the Netherlands. I will try and find out more about alternative bearings with more rollers.

 

Wayne the clutch housing bearing diameter 70mm. Sleeve diameter 64mm. Bearing depth 23mm. I am interested in the engineering aspect. Does that mean a K64mm X 70mm X 23mm will fit and if so what about clearance? Does the bearing have enough clearance or is a C3 bearing needed for example?

 

I would say the sleeve diameter, housing diameter and width is all you would need. So the needle bearing would be about 3mm. I think the needle bearing is sized for the sleeve and housing. I would probably talk with a bearing supplier for addition answers. I will google some questions about that.

 

The only bearing I could find is a 64x70x16 so it may be a special bearing made for Yamaha

 

The nearest size I found is 65x70x20.

 

Probably need to talk to the bearing supply people to see if its a std bearing size.

 

I will but l don't think it is.

 

Fewer rollers = less friction/resistance. As long as the rollers are sufficient to support the radial load, then all is well. Roller bearings support far greater loads than a similar size ball bearing and can run more successfully at much higher speeds.

 

Its the load I would be concerned with. I have not seen a bearing like that with so few rollers. I think they could have doubled the amount in that bearing.

 

So far l not found an alternative bearing.

 

Same with me