Grease in swinging arm - take it apart or not ?

Hello,

I am new on the board, but I'm reading for quite some time. I am from Germany and I have a 850 MK2 since 2 years,
which I have nearly completely rebuilt, with exception of the swinging arm.
There was no need yet, because it still has no play. But the PO has greased it, so I continue greasing it.
I know, that it's wrong and that there are a lot of threads about it. But what chance do I have ?
If I would take it apart to clean, the bushes could be replaced at the same time.
So I could wait until I detect some play.
The problem everybody is worrying about is to get play between spindle and cradle.
But would the usage of 140 oil prevent this?
I think no, because the oil would not get into the cradle anyway. And the spindle normally doesn't move in the cradle.
So it needs no lubrication.
Another question is: which play will normally occur first - in the bushes or in the cradle ?
But independent of this answer, IMHO there is no reason to take the swinging arm apart as long as no play can be detected.

Ralf

Welcome to the forum, Ralf.

Towner said:

I am new on the board, but I'm reading for quite some time. I am from Germany and I have a 850 MK2 since 2 years,
which I have nearly completely rebuilt, with exception of the swinging arm.
There was no need yet, because it still has no play. But the PO has greased it, so I continue greasing it.
I know, that it's wrong and that there are a lot of threads about it. But what chance do I have ?

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Up to you really, but the bushes are relatively cheap, and if there's no play, maybe clean as much grease out as you can and then use oil.

Towner said:

The problem everybody is worrying about is to get play between spindle and cradle.
But would the usage of 140 oil prevent this?

Click to expand...

One of two things usually happens, either the spindle eventually becomes loose in the cradle or, it rusts soild inside the cradle tube.

Towner said:

Another question is: which play will normally occur first - in the bushes or in the cradle ?

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It's often the spindle that becomes loose first, but not on every occasion.

The Mk3 pivot assembly is "sealed for life" therefore I guess your Mk2 probably does not have the Mk3 type assembly if you are able to lubricate it.

Thanks for the detailed answer !

It has sadly not the double cotter pin spindle location. It's from 73.

Could a damaged cradle be a result of riding with worn bushes ?

I think you will get many opinions on this one Ralf, and as you've read the many threads on forum, you'll know what the options are. As you say, play can be between the Bushes and the spindle, or/and the cradle tube and the spindle.

My understanding is that play between the cradle tube and spindle, on a pre-mk3 model(LAB says late mk2 are also ok so it will be correct) , will worsen over time due to the poor design utilising a single bolt in the middle of the spindle. It would be prudent to stop this happening whilst the cradle tube is still in good condition, and you'll see the many good threads showing how to fit the clamps. I followed this one which I thought was good for average mechanic, and looks like a good job. http://www.doov.com/apps/nortoncomp...=4:swingarm-spindle&catid=1:upgrades&Itemid=8.

Whilst doing the clamps mod, the spindle/caps/bushes get stripped down, mine were pretty gunged up, and looked like they had been greased in the past, so they all get serviced at the same time, and you'll be back to using oil for the bushes.

So, in answer to your final point, if you are happy with the amount of play at the moment you're right in saying that you can continue to ride, but maybe expect to do some work later if the play worsens. The way I looked at it was if I had time to do the work before the bike was rebuilt, then fitting the clamps, and sorting out the lubrication means (hopefully) eliminating problems later on.

Grease is about the best lube to put on slow short arc high load applications, IF you can actually get grease in the working spaces, which requires modification of the factory oil fed system d/t small holes and un even grease flow if fed on one side only just oozes out that side leaving the other dry. Follow the advice given for stablizing spindle after caked grease cleaned out so oil can flow in and out to the ground via bushes space to retain some left overs a while in the bush pores.

Both my Cdo's are greasers now so I can be more lazy maintainer than others for a number of reasons.

Thanks all for your answers. I know, that I have to do the job some day, at the latest when I have to take apart the primary case next time.
I have not decided for a special repair method yet. Welded nuts are a good solution too, as an alternative for the clamp method.
Next job for this year is to replace the master cylinder with the Andover type.

Ralf

Edit: @Hobot: The grease conversion is a good solution indeed !

the great swing arm lube conversion!

the holes in the spindle are very small, maybe 1/16th inch or so, so doubtful any grease you have in there now has even found its way down those holes to provide additional lube to the original bronze oil soaked bushings


when Heinz Kegler and I removed my swing arm a few years ago Heinz smeared the entire spindle with some anti-seize

he commented that the very short travel of the swing arm at that point was so minimal that any wear was localized


I only put on about 1500 miles a year puttering about so Heinz told me not to bother with spindle lube as the thick and sticky anti seize would likely keep things just fine for some years, especially given that he had also installed his swing arm aluminum rings on my bike.

he did like the Mark3 solution best of all

Run it until it loosens... Then rebuild as needed. This coming from a person with WAAAYYY too much machinery to keep running! :lol: YMMV

concours said:

Run it until it loosens... Then rebuild as needed. This coming from a person with WAAAYYY too much machinery to keep running! :lol: YMMV

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Yes, that's what I want to hear :lol:

The problem is I have no proper workshop, only a car garage. It is no fun to work there in winter. So have to prioritize what job to do first. It has to be urgent or should be completed on a Saturday morning.

Ralf

I run a gravity feed of 90 oil from a 30ml bottle under my seat on bth othe the 750 and 850. I brazed a 3/16 copper pipe to a bolt i had drilled out for the 1971 750. This fitted into the grease nipple hole on the right hand side. a length of nitrile tube runs up to the bottle, which i top up occasionally. I drilled a small hole in the centre locating bolt on the 850 and brazed a piece of 3/16 copper pipe to that. They both leak a little but i figure they must be being lubricated if they leak.

"They both leak a little but i figure they must be being lubricated if they leak."

Ah...the classic Brittbike oil level indicator - if it's not leaking, it's out of oil!

The easy factory intended way to oil the older style Cdo spindle is with a oil pump 'gun' that fits on the nipple provided. I tried the big sight tube feed method, to realize even with perfect race grade machined and fitting cradle and new swing oil and seals, it just all drools out even un ridden in winter too cold to hold tools w/o dang gloves or feel limbs d/t wind.

I am relieved by Hienz using thin anti-sieze and saying it could last a few years, as I've gone over a year w/o greasing my modified spindles and wondered if I was letting it wear out too soon again, but nope.

I thought my 850 shock springs were too stiff when I bought the bike off my fat ex-friend. Not the case.
The idiot had been greasing the swing arm all the years he owned it. There is evidence of different colour grease in there.
However, none of the grease reached the place that need it.
Consequently the spindle on the drive side rusted big time, that rust penetrated the bushing bonding into it and forced the bush to rotate in the swing arm.
It was a bit tough removing the assembly but out it came with a bit of brute force. I knew it must be rooted so I had nothing to lose doing it that way.
Another poor design to rethink and improve on.

Throber said:

I thought my 850 shock springs were too stiff when I bought the bike off my fat ex-friend. Not the case.
The idiot had been greasing the swing arm all the years he owned it. There is evidence of different colour grease in there.
However, none of the grease reached the place that need it.
Consequently the spindle on the drive side rusted big time, that rust penetrated the bushing bonding into it and forced the bush to rotate in the swing arm.
It was a bit tough removing the assembly but out it came with a bit of brute force. I knew it must be rooted so I had nothing to lose doing it that way.
Another poor design to rethink and improve on.

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Not so much a poor design as poor maintanence. Its's not suppose to have grease in there.

As Herb Becker and Doug MacRae found on a real isolastic racer, even silvery thin anti-seize lasts a long time in swing arm protection, so grease is the ideal lube there, if made to get grease to the bushes and bushes grooved to spread it out. The factory had a pretty good system in the 750's, just use an oil pump instead of grease gun to put oil in the spindle cover zerk. This is what I did for a while until I converted to greaser and sold off the British oil pump which looked like a small grease gun.

GUN OIL/GREASE POM POM

Mr Pvisseriii, I know it's not supposed to have grease in there but not everyone does, evidently.
I think the swing arm is a poor design on the 1973 850, that is why there are so many mod's being done to bikes by owners.
My Venom has grease nipples and works well.
The Norton loses the swing arm oil immediately you put it in. Seem's to me not to be a good design.
Not to mention the need to pin the spindle to stop it moving all over the place.
Then there is that silly two piece rear axle. No wonder Commandos wobble at speed. But that's another bitching session to be held else where.


Thinking of the people of Boston. Ye god's !

Grease plugs up the tiny lubrication holes. Plus the spindle is not secured tight enough.

Throber you got some good preaching phrases on all the early splndle sins and how to avoid them , but you done gone to meddling in my personal affairs with suggestion the split axle has anything to do with Cdo handling, until it breaks and even then only a flat tire like bother the first few mph taking off then nothing, if holding a steady easy steering hand. On that note though, bad wheel and drum bearings that have lost grease undetected can beat dumb axle into the dark side faster.

Actually since grease lasts so long in this type application and makes splindle an easy in/out job, might just shape tree it by spiral grooving the bushes and hand slathering grease on and shove er home every year or 10,000 miles or so.

Now we need to find out the best grease to use and why not to mix em, at least in bearings but prolly a non issue in plain ole bushes.

Usually the pins, and not the bushings, wear because the bushings pick up grit that is harder than the pin. So, to escalate the war between materials of dissimilar hardness, hard chrome the pin, now the bushings might wear.

I've seen a couple of the worse ever spindles and can't deny that its grit that accelerates splndle wear but its not form stuff getting in from outside but the self generated crusty rusty corrosion decay of unprotected but humid super hardened steel layer that a good file should not scratch. It you've not had to deal with a spindle swollen tight with rust + with deep lips worn in both end of spindle by soft bushes holding the grinding grit so completely trapped - I always reflex on the next generation after me, to keep er greased on couple times a year flood with oil to stiff rust. I've left my spindle out open in living room motorcycle shop to find it getting a rust stain patina so oil and wrapped up when not greased and slipped into waiting Ms Peel to finish me off.


LIkely the easier way to go greaser would be just use the factory oil zerk and open up spindle holes to flow some grease and not pack up plus spiral groove the bushes to spread it out enough not to rust then wear in spots. I suppose its possible to blow the end cap off the tiny bolt threads but it should show grease mooshing out well before that.