Swingarm Lube. . . No Zerk Fitting.

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Bonwit

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I wonder if someone can shed some light on what the deal is with my '74 850's swingarm pivot. I went to lubricate it for the first time and found that mine doesn't look like the manual. The photo below is of the right side and as you can see, the end cap is a blank plug. No Zerk fitting. Is this a modification? If so, does it need lube and if so, how?
Thanks
Swingarm Lube. . . No Zerk Fitting.
 
You are going to need to somehow get that sucker out (I'd order a new one first, then not worry about damaging the old one).

Use 140 gear oil, NOT GREASE!!!!!!

If you get the plug off and there is grease in there, you are going to need to pull the shaft and clean it out COMPLETELY. Then fill 'er up.

If it didn't have grease in there, tip the bike over and fill it, then plug it. smear a dab of RTV silicone around the edge and let it cure.
 
This is the 850 MK3 version of the swingarm lubrication but introduced during the 74 model year, follow GP's instructions but before you refit the blank plug drill tap it and fit a zerk fitting, no need to remove it next time you need to lube it.
 
So are you supposing that a PO packed grease in there and capped it off? Great!

Looking at the parts manual, I see that there is an End Cap Rod that appears to run through the cap. Obviously, I don't have that either. What does it do? Does the replacement cap come with the Zerk fitting already in place, or do I have to drill and tap for one?
 
Bonwit said:
I wonder if someone can shed some light on what the deal is with my '74 850's swingarm pivot.
Click to expand...

Many late MkIIs and all MkIIIs had 'sealed for life' pivots, containing felt retaining wicks that were hopefully soaked with EP140 oil on assembly, therefore theoretically these pivots require no maintenance.

Here is MkIII assembly (which has twin cotter pins instead of a single bolt) : http://www.nortonmotors.de/ANIL/Norton% ... &Plate=016

However, if the (MkII) spindle retaining bolt is unscrewed from the cradle, oil can be added through the bolt hole.
 
Bonwit said:
So are you supposing that a PO packed grease in there and capped it off? Great!

Looking at the parts manual, I see that there is an End Cap Rod that appears to run through the cap. Obviously, I don't have that either. What does it do? Does the replacement cap come with the Zerk fitting already in place, or do I have to drill and tap for one?
Click to expand...

You need to look at the MkIII parts book for some of the parts on your bike.
 
The plugs are just like freeze plugs in a car motor and iirc, there is a common freeze plug that can be used as a replacement. You have to punch a hole in the plug (can't get to the drive sider without removing the chaincase) and pry it out to get to the felts. There is a felt plug that goes into the pivot shaft and a felt disc that covers the end. The plugs are slightly concave and must be flattened with a large flat-faced drift which expands them into the end of the pivot tube. Lube can be dripped into the fixator bolt bosses, but it's a slow process since 140 is pretty thick. I replaced the plugs on my Mk III with a 750 setup that has a threaded cap on the drive side, a zerk on the timing side with a long skinny bolt that holds the two sides together. The felts must be eliminated to be able to pump lube through the zerk and fill the pivot shaft.
 
Having a zerk on there is great... I keep a small grease gun that I use 140 weight gear lube in, solely for the swingarm. Note, the lube will leak out of the gun over time (guess they really are made for grease, loose tolerances) over time so it's best to fill the gun with a small quantity at a time. Works a treat.
 
I'm in agreement that my set up is indeed factory and that it's supposed to be this way. Now my question is, have these "sealed" setups held up over time? If so, I'm inclined not to mess with it, though figuring out a way to drip some 140 wt. through the fixing bolt hole seems like a good idea.
 
You don't need a s@@@load of lube in there, so maybe you could heat it up a little (to thin it) and drip some in via the fixing bolt hole using something like one of those little "syringe" and hose jobbies used to reverse bleed brakes? Just a thought.

Just don't let the swingarm move while the bolt is out of there. When I did the Heinz Kegler swingarm mod on my bike, the hardest part (the only hard part) was getting the bolt back in there and into the spindle. Aligning those holes was a biotch. I finally did it using allen wrenches to check the alignment (on a "go/no go" basis) but it isn't something I want to do again soon.

Best of luck.
 
Bonwit said:
I'm in agreement that my set up is indeed factory and that it's supposed to be this way. Now my question is, have these "sealed" setups held up over time?
Click to expand...

I've never touched the sealed assembly on my MkIII, and the pivot is still as tight as it was when I bought my Commando over 10 years :shock: ago, and I have no idea when the pivot was serviced prior to that, although I have to admit that I don't put an awful lot of miles on my Commando annually, generally because work, the UK weather, and having a number of other bikes to ride all conspires to limit its mileage (excuses- I hear you say!) plus I already have enough spare spindles and bushes on the parts shelf to see me out!
 
My 74 is exactly the same. The MKII swingarm has the welsh plugs in the ends and there are felt washers and wicks inside that absorb oil like the MKIII style.

Do NOT take the end caps off. You fill the cavity through the central fixing bolt that's on top of the swingarm pivot tube. I use a pump type oil can or a plastic syringe with a small length of hose. Fill it veeery slowly until oil no longer bubbles down the hole. Best done with the rear wheel off.

The bad news is that the oil will leak out around the rediculously designed "seals" between the swingarm and cradle. The good news is that the felt wicks do their job well.. my spindle and bushings looked like new when I inspected them a couple of years ago.
 
maylar said:
The bad news is that the oil will leak out around the rediculously designed "seals" between the swingarm and cradle.
Click to expand...


Some while ago, I formed the opinion that the primary function of the 'seals' was to keep water and dirt out of the assembly, rather than to prevent any excess oil from draining away.
Oilite (sintered bronze) is highly porous, therefore Oilite will absorb all the oil it needs in order to function for a fairly long period of time, so there's really no need to keep Oilite bushes constantly "wet" with oil in order for them to do their job. The early system only requires periodic re-lubrication, and the later sealed system with the felt wicks in theory at least, should not require any maintenance at all for several years.




http://www.mct-eb.com/pdfdown/Oilite.pdf
"Oilite is a metallic sponge with the lubricant stored
in the interconnected pores of the bearing.
Capillary action holds the lubricant in the bearing
and prevents it from dripping. Pressure and/or
heat applied to the bearing brings the lubricant to
the surface where it forms a protective oil film or
optimally a hydrodynamic wedge between the
bearing and the shaft."
Click to expand...
 
My Mk I 850 has a Mk II swingarm that looks like the one above. It has the sealed caps and Mk III-type seals, but the single fixing bolt rather than the cotter pins. I used a self-tapping framing screw to drill into the center of the right side cap, and re-oil every several thousand miles by removing the screw and topping off with a syringe filled with warm 140 Wt oil into the hole. I know it has the wicks and oilite bushings, as I rebuilt it. This is also how I learned its the later swingarm, as I bought the Mk I-style o-rings and dust boots first, and had to exchange them for the Mk III-style seals.
 
BillT said:
and re-oil every several thousand miles by removing the screw and topping off with a syringe filled with warm 140 Wt oil into the hole. I know it has the wicks and oilite bushings, as I rebuilt it.
Click to expand...
Someone suggested that it might be difficult to get the oil past the felt. Have you found this to be the case? Could you not accomplish the same thing by injecting warm oil through the fixing bolt hole? It doesn't seem like it needs much. Since there's no other choice, you would think this is what the engineers intended (unless "sealed for life" means just that).
 
Bonwit said:
BillT said:
and re-oil every several thousand miles by removing the screw and topping off with a syringe filled with warm 140 Wt oil into the hole. I know it has the wicks and oilite bushings, as I rebuilt it.
Click to expand...
Someone suggested that it might be difficult to get the oil past the felt. Have you found this to be the case? Could you not accomplish the same thing by injecting warm oil through the fixing bolt hole? It doesn't seem like it needs much. Since there's no other choice, you would think this is what the engineers intended (unless "sealed for life" means just that).
Click to expand...

I don't trust any engineer that says "sealed for life" because there is a marketing guy behind them saying "sealed for the length of the warranty".
 
Bonwit said:
Since there's no other choice, you would think this is what the engineers intended (unless "sealed for life" means just that).
Click to expand...

The 1970-73 factory manual routine maintenance section recommends: "Check and oil the swinging arm bushes" every 6,000 miles, and to "Check the swinging arm spindle" at 12,000 miles.
The MkIII manual (therefore "sealed for life" assembly) does not contain any recommendation to "Check and oil the swinging arm bushes", only "Check the swinging arm spindle" at 12,000 miles.

The MkIII 'Frame and ancillaries' section, concerned with the replacement of the sealed S/A pivot bushes, contains the following paragraph :

Remember you will need new welch-washers and must ensure the "plug-wicks" and felt discs are fully impregnated with SAE140 oil before assembly. These must provide lubrication, for life, of the replacement bushes !
Click to expand...

(and the exclamation mark is part of the original manual text)
 
swooshdave said:
I don't trust any engineer that says "sealed for life" because there is a marketing guy behind them saying "sealed for the length of the warranty".
Click to expand...

"Sealed for life" is approximately equal to "one size fits all." And we all know THAT is BS....
 
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