Sealed swingarm pivot

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Chester

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Mar 28, 2010
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Hi guys,

I have the swingarm with the sealed ends ( ''74) .
I did the drill and tap to remove the one side. Those felt wicks don't seem to be available.( Brit Bike Supply NS)

Do you guys make your own felt washers and wicks and such?

The pivot seems to be a sealed unit, and I guess it gets oiled up and just stays like that till the next bushing replacement?
 
I can't quite figure out that arrangement...you put felt wicks inside the swing arm spindle. The felt wicks are soaked in 140 oil. Then you seal it up. But the oil is soaked into the wick and the wick does not bear directly on the bronze bushing. How the heck does that lubricate anything?

Normally, in a felt lubrication setup - common on elec motors -the felt is in actual contact with the bronze. There is wicking action from the oil-loaded felt to the bushing so there is film of oil being transferred from felt to the porous bronze. The way the MkIII looks to me the felt is NOT in contact with the bushing. The steel spindle is not porous so although there would be a film of oil on the inside of the spindle where the felt touches it, there would be no tendency that I can see for any of the oil to then somehow magically migrate to the bushing.

Or do I misunderstand how it actually functions?
 
Sealed swingarm pivot


Look at 3 and 12. Two wicks. One inside the spindle and the other against the bushing. Don't ask me how it's suppose to work. I'm of the camp that an oil impregnated bushing should be good for a while without any help.
 
mike996 said:
I can't quite figure out that arrangement...you put felt wicks inside the swing arm spindle. The felt wicks are soaked in 140 oil. Then you seal it up. But the oil is soaked into the wick and the wick does not bear directly on the bronze bushing. How the heck does that lubricate anything?

Or do I misunderstand how it actually functions?
Click to expand...

The cylindrical felt "wick" [12] may not actually bear directly against the bush, but the felt "disc" [3] does, and the wick would normally be in contact with the disc because even with the wick pushed fully home inside the spindle, it still protrudes from it by approx. 1/8".

So there's your lubrication path.
 
The swingarm axle is hollow and there is small hole cross drilled at each end. The oil reservoir provided by wicks seeps into the holes and through to the bushings. if you are ever fitting new bushes, it pays to soak them in hot oil for a few hours that way they will retain lubrication for ages.

mick
 
ML said:
The swingarm axle is hollow and there is small hole cross drilled at each end. The oil reservoir provided by wicks seeps into the holes and through to the bushings.
Click to expand...

I've just checked three MkIII type spindles, none of which have any cross-drilled holes in them.
 
L.A.B. said:
ML said:
The swingarm axle is hollow and there is small hole cross drilled at each end. The oil reservoir provided by wicks seeps into the holes and through to the bushings.
Click to expand...

I've just checked three MkIII type spindles, none of which have any cross-drilled holes in them.
Click to expand...


Original or reproduction?
 
swooshdave said:
Original or reproduction?
Click to expand...

I don't know.

But they are all old stock, and I think they all came from different sources, but I don't see that a cross-drilling is going to do anything that the felts wouldn't?
 
Frankly, it seems to me that a MKIII swingarm "upgrade" would be to convert it back to a MKII ! :)
 
My '74 MKII has a MKIIA swinging arm. The spindle is the same length as the MKIII (shorter than earlier models) but without the flats. It has the tapped hole on top and small holes on each end. The bushings are MKIII (different length than earlier also).

The felt wicks and discs (items 12 & 3) take a LOOONG time to soak up 140 weight. I had them in a cup for a week and they still were only coated on the outside. Fortunately the MKIIA still fills up the spindle through the fixing bolt hole, so you can keep adding (and leaking) oil until you're confident that they're saturated. The good news is that my bushings and spindle were perfect when I inspected them after 34 years. The oil scheme seems to work well.
 
L.A.B. said:
ML said:
The swingarm axle is hollow and there is small hole cross drilled at each end. The oil reservoir provided by wicks seeps into the holes and through to the bushings.
Click to expand...

I've just checked three MkIII type spindles, none of which have any cross-drilled holes in them.
Click to expand...


The one I installed is made for all models, and if you look carefully at the lower end of the pin, you can just make out the tiny oil hole. Why this obviously useful feature was not put into Mk3 pins is somewhat of a mystery to me. But then again its not the only odd thing Norton have done!


[url=http://i884.photobucket.com/albums/ac47/ml850mk2/SwingarmMk3.jpg]http://i884.photobucket.com/albums/ac47 ... armMk3.jpg[/url]
 
swooshdave said:
ML said:
Bugger why that pic didn'ty post first time????????

Sealed swingarm pivot
Click to expand...

IMG tag was in the wrong place.

I assume you're going to use the same clamping I did?
Click to expand...

Swoosh, - I went with the welded lock nuts, then line reamed to .005 O/S. Its a good firm fit and plenty of room between the swingarm cross brace.

Sealed swingarm pivot
 
ML said:
Swoosh, - I went with the welded lock nuts, then line reamed to .005 O/S. Its a good firm fit and plenty of room between the swingarm cross brace.
Click to expand...

Nice job.
 
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