Oiling the swingarm bushing.

[Joe Schlaberdowski]

The swing arm on my bike has a zirk fitting at one end. I hadn't oild it and, after having a flat rear tire upon just setting out, I decided it was time to oil the swing arm. There is a small bolt on top of the swing arm bushing housing and I couldn't get to it unless I removed the fender AND the horn! I have a nice new oil gun (looks like a grease gun, but a lot more expensive -- don't know why the extra expense) So I tried to pump in some 90/150 -- and couldn't! Took off the zirk and pushed like crazy on the gun lever expecting the zirk to fly off in to space. Finally some oil came through, and then a little more. The hole that gets closed by the ball bearing in the zirk is much smaller than for grease zirk fittings. Put it back on the end of the swing arm and started pushing for all I could. Out of the small bolt hole on the top of the bushing came a red grease like stuff. I pumped till it was just oil coming out. Now the question. Was that a thickened heavy red oil turning into a grease like substance after 45 years or had someone loaded this up with a red colored grease? I was told that grease clogs the porous bearing, clogs the pores. Now it's not exhibiting any problems like sticktion or noises or lack of movement. Just wondering if thick oil can actually thicken like that. Or was that a special grease you could use and not worry.

 

[L.A.B.]

Or was that a special grease you could use and not worry.

Probably grease but nothing special about it.

 

[Craig]

Maybe take SA apart , inspect and replace what needs to be , in your next off season .... once all cleaned up inside fill with new oil and place newspaper under that area when on centre stand , good to go .... ... against most opinion I followed Hobot back in the day and used grease when I redid mine , been afraid to take a look ever since , guess I will one of these coming long winter nights ... Good luck with yours

 

[kerinorton]

My 2 bikes have gravity fed 90 oil going through that centre bolt on the 850 or through a replacement bolt where the zerk fitting is fitted, on my 750. Both bolts are drilled and have a 3/16 OD copper tube brazed to them with a length of 3/16 ID neoprene hose connected, and joining up witha 30 ml bottle of the 90 oil. Easy. I fill it up maybe twice a year or before a long ride.

 

[MexicoMike]

It appears the previous owner used grease rather than oil. But sounds like you've 'cleaned out' the grease, which is good! BE CAREFUL when pumping oil into the swingarm in the future. If you attach a grease gun with oil in it to the Zerk fitting, you can exert enough pressure to strip the threads on the long, thin screw that holds the end caps on the swingarm and blow the end caps off the swingarm!. This is a major PITA because access to the primary side of the swingarm to reinstall the cap after purchasing a new screw is rather difficult!

I have the T-shirt for that particular operation!

What was particularly annoying for me was that the blow-out occurred AFTER I had pulled the Swingarm, installed new bushings, put it all back together and then pumped in oil!

 

[kommando]

Only pump in oil if the displaced air has an escape route.

I put the bike on the sidestand so the grease nipple is at its highest, undo and remove the grease nipple and then use a EP90 filled oil can to slowly dribble oil in the hole while looking at the air bubbles exiting the same hole. Once the bubble stop I refit the grease nipple. I do this annually, once the bushes are soaked for a day or so they retain enough oil for some time so a constant supply is not needed.

 

[marshg246]

Out of the small bolt hole on the top of the bushing came a red grease like stuff. I pumped till it was just oil coming out.

Unfortunately, you most likely accomplished very little. The timing side of the spindle is probably now full of oil, but the drive half isn't and the tiny holes that let oil get into the bushings are probably still clogged with grease.

 

[MexicoMike]

Well...probably true though better than it was. Obviously, the best thing to do would be pull the swing arm and either thoroughly clean the existing bushings or install new ones.

 

[Joe Schlaberdowski]

Well...probably true though better than it was. Obviously, the best thing to do would be pull the swing arm and either thoroughly clean the existing bushings or install new ones.

At this point I'm probably not going to take it all apart. With the shocks disconnected I'll see if it moves ok. I'll look in one of my manuals to see how hard it is to take it apart to clean it. But say I do get it apart, are the bearings a press fit on the swing arm? And with the bearings off, or still pressed onto the swingarm, how do you clean bearings of pressed in grease? I'm imagining just a surface clean with gas or whatever your choice of poisonous solvent (my go-to is gas. Sorry if that's too crude) might not get down in the porous material.

 

[ILLF8ED]

My approach is a bit different, but safe. Remove the zirk. Fill with 90wt through the small hole using a sports ball inflating needle connected to a plastic syringe. It’s slow, but works.

 

[chaztuna]

snipped
Out of the small bolt hole on the top of the bushing came a red grease like stuff. I pumped till it was just oil coming out. Now the question. Was that a thickened heavy red oil turning into a grease like substance after 45 years or had someone loaded this up with a red colored grease? snipped

Joe,
Certain brands of marine wheel bearing grease are red. These products are designed to protect the wheel bearings on boat trailers, which are regularly submerged in water. So if it is grease, the previous owner at least had the sense to choose a water proof product. Redline's petroleum products are all dyed red, so it could be Redline Synthetic Gear Oil for manual transmissions.

https://www.redlineoil.com/75w140-ns-gl-5-gear-oil

This is an excellent product. If the red lubricant is the above oil, odds are what you added is inferior. Either way, because it's red in color, it has not been in there for 45 years.

Charlie K

 

[chaztuna]

snipped
But say I do get it apart, are the bearings a press fit on the swing arm? And with the bearings off, or still pressed onto the swing arm, how do you clean bearings of pressed in grease? I'm imagining just a surface clean with gas or whatever your choice of poisonous solvent (my go-to is gas. snipped

Joe,
Yes, the bushings are a press fit in the swing arm. Odds are that they will need to be line reamed after installation. A machinest can probably do that for you for less than it will cost you for the appropriate reamer. Avoid the urge to open the bushings up using sand paper or emery cloth. That removes excess metal and introduces abrasive grit into the bushing. [exact opposite of what you are trying to accomplish] Gasoline [aka petrol] will work for cleaning the bushings. My personal preferance is to use aerosol brake parts cleaner. When it evaporates, it takes the grease/oil with it and leaves no residue. Best of all, I didn't get my hands covered in gasoline.

Charlie K

 

[Joe Schlaberdowski]

Joe,
Yes, the bushings are a press fit in the swing arm. Odds are that they will need to be line reamed after installation. A machinest can probably do that for you for less than it will cost you for the appropriate reamer. Avoid the urge to open the bushings up using sand paper or emery cloth. That removes excess metal and introduces abrasive grit into the bushing. [exact opposite of what you are trying to accomplish] Gasoline [aka petrol] will work for cleaning the bushings. My personal preferance is to use aerosol brake parts cleaner. When it evaporates, it takes the grease/oil with it and leaves no residue. Best of all, I didn't get my hands covered in gasoline.

Charlie K

The "red stuff" came out the top hole looking extremely clean. It was a translucent red. Not heavy grease kind of light. Unfortunately my son wiped it up before I took a good look at it. I imagine wheel bearings such as in the wheels of boat trailers made to go down a ramp and into the water are ball bearings, not bushings. But I would be glad to know I'm wrong about that. There was (maybe still is) a product for good bicycles called Phil Woods Waterproof Grease. I rode bicycle a lot and did all my own maintenance. I always used it. Bicycles use ball and sometimes roller bearings. It became difficult to get and, on the internet, I found that it was a product similar to what you have described. This product was a dark green however. I'll get in touch with the company you listed and ask about plain bearings. Now, it's still not certain we're talking about the same product, but I'll try to find out. Maybe they're the guys that made Phil Woods grease!

 

[chaztuna]

I had a brain fart on my post #11. Note to self. Be sure to take your Ginko Biloba prior to posting on web forums! The Redline product linked would be best used in the gearbox. Better to use their 80/140 Gear Oil for the swing arm bushings, as it contains extra extreme pressure lubricants, not in the gearbox oil. It's also a bit thicker, as Norton originally called out straight 140 wt gear oil. Perhaps this would be better? See

https://www.redlineoil.com/80w140-gl-5-gear-oil

If it is grease, remember that "back in the day" trucks used king pins, rather than ball joints. King pins use bronze bushings, with Zerk fittings to allow them to be re-greased.

Charlie K

 

[Joe Schlaberdowski]

I had a brain fart on my post #11. Note to self. Be sure to take your Ginko Biloba prior to posting on web forums! The Redline product linked would be best used in the gearbox. Better to use their 80/140 Gear Oil for the swing arm bushings, as it contains extra extreme pressure lubricants, not in the gearbox oil. It's also a bit thicker, as Norton originally called out straight 140 wt gear oil. Perhaps this would be better? See

https://www.redlineoil.com/80w140-gl-5-gear-oil

If it is grease, remember that "back in the day" trucks used king pins, rather than ball joints. King pins use bronze bushings, with Zerk fittings to allow them to be re-greased.

Charlie K

Same for my Healey 3000. There are bushings. And there are zirk fittings! Along with grease clogging the bronze bushing, maybe they use oil (albeit heavy gear oil) to make sure lubrication gets to all parts of the bearing. If it's a close fit I could see the bushing squeezing out all the grease leaving a poorly lubricated patch.

 

[L.A.B.]

I would have thought the timing-side end cap could be removed and the worst of the grease in the spindle cleaned out?

Phosphor bronze is often lubricated with grease, however, sintered bronze (Oilite) is porous and readily absorbs oil.
If grease is pumped into the swingarm then it won't reach the bush on the opposite side.

Here a drop of oil is completely absorbed by a dry sintered bush in no more than a few minutes leaving no trace left on the surface of the bush!

 

[Joe Schlaberdowski]

I would have thought the timing-side end cap could be removed and the worst of the grease in the spindle cleaned out?

Phosphor bronze is often lubricated with grease, however, sintered bronze (Oilite) is porous and readily absorbs oil.
If grease is pumped into the swingarm then it won't reach the bush on the opposite side.

Here a drop of oil is completely absorbed by a dry sintered bush in no more than a few minutes leaving no trace left on the surface of the bush!

That was interesting. Very. Another test needs to be made. Take a bronze bush that was run in grease. If there was no lubrication at any spots (no grease left, all squeezed out from patches leaving no lubricating film, put oil there and see if there is any absorbtion of oil. Then take a bronze bushing that was run in grease, clean it with whatever solvent you wish. I actually have an ultrasonic cleaner normally used with ammonia. Not a household product, but a very strong ammonia. I would, however be afraid of ammonia now getting in there. Probably best to use brake clean or good ole gas. Now, with the bushing ostensibly deep cleaned, try the oil drop test again. Purpose is to see if grease really does ruin it and to see if cleaning in any kind of normal way can restore it. I'll bet it takes less time to run the test than to write it out. The results would either make a few people happy, or depress them.

 

[Super Seven]

So is there any movement side to side? If not, whatever it was seems to have worked. I can't say the same for my MK II. Videos I have seen on this site all showed only bushing wear, not seized bushings enlarging the holes in the cradles.

 

[marshg246]

Here's what I would do. Stick a piece of cardboard between the inner primary and swingarm so the drive side end cap is held in place. Remove the through bolt and timing side end cap. Use something to support the swingarm/rear wheel. Pull the spindle and clean it - especially the little oil holes. If it looks OK, put it back together and fill with oil. It's about a 30 minute job. If the spindle is damaged, get a new one, new bushings, and new O-rings - it is not hard to change the bushings - they are a light press fit.

 

[L.A.B.]

Another test needs to be made. Take a bronze bush that was run in grease. If there was no lubrication at any spots (no grease left, all squeezed out from patches leaving no lubricating film, put oil there and see if there is any absorbtion of oil. Then take a bronze bushing that was run in grease, clean it with whatever solvent you wish.

I also don't see the need to get too scientific. Just remove as much grease as possible (if that's what it is) and fill with oil.