My swingarm bearings never leak oil – Something new to try (2014)

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My swingarm bearings never leak oil – Something new to try (2014)


I designed a dry running replacement for the oilite swingarm bearings for my 1970 Norton Commando when I did my rebuild. This bearing has been a pain for some Norton owners as it is prone to wear and has a questionable lubrication method and poor holding of the lubrication which has been the subject of many Access Norton discussions. There are other issues with the swingarm design but I am getting off topic.
The bearing is a direct drop in replacement for the bearing that is there. It is a grooved and graphite-filled bronze flanged sleeve bearing which I had machined at a bearing manufacturer to my specifications.
Graphite-filled groove bearings have graphite in the grooves, which acts like on-board lubrication without the oily mess. It is made of Alloy 932 which is a nonporous cast-bronze material that is hard, strong, and abrasion resistant. It also offers excellent resistance to shock loads and wear. Do an internet search for more information.
Technical stuff: Bearings are rated in PV (Pressure-Velocity)
SAE 841—Also called Oilite is porous material is impregnated with SAE 30 oil. It is made by powder metallurgy so 19% is air space (think sponge). Not very strong.
SAE 841 (Oilite) 2000 P max,1200 V max,50,000 PV max rating
Alloy 932, 4,000 P max,750 V max,75,000 PV max rating
Since the bearing is in a pressure environment in the swingarm (oscillating not rotating) My bearings have double the load rating of the existing oilite assuming proper lubrication.
I have some bearings left over (had to buy a small lot) that I have installed on my bike which has not been ridden much this year since the install. The bearings are nice and tight. Because the bearing is made from a stronger material it is a bit harder to install so I recommend an installation tool (just a fully threaded bolt, nut, and washers that are also good for removing the old shaft). You also need some graphite powder which you can get at any auto parts store. I don’t know how well it will fit all the Norton Commandos. The 1975 has shorter bearings so I think a custom end cap is needed. Like I said, if you are OK with a prototype design (do your research), I will sell the leftovers for $25 each. Preference will be givin to those doing a current rebuild that can provide me some feedback. I have made provisions with a local Philly Brit Bike shop to distribute. http://quakercitymotorworks.com/norton- ... arm-bushes. . Will provide installation instructions too.
If there is enough demand I will take orders and purchase another lot. About a four week lead time.
I welcome any feedback from the outspoken Norton enthusiasts. If there is demand for an special oversize bearing version or an exact match for the shorter 1975 bearing let me know. It is going to be one less oily spot in your driveway.
 
Re: My swingarm bearings never leak oil – Something new to t

Wow with such attention to this bush upgrade I'll take two immediately to see how they fit in my living room Commando which has got to take some pounding with extra range of motion. I'm a greaser from the '50's so likely will use graphite grease.
 
Re: My swingarm bearings never leak oil – Something new to t

To clarify - There is no additional grease or oil required. Completely dry running with some added graphite powder and impregnated graphite in grooves as shown in picture.
 
Re: My swingarm bearings never leak oil – Something new to t

hobot said:
Wow with such attention to this bush upgrade I'll take two immediately to see how they fit in my living room Commando which has got to take some pounding with extra range of motion. I'm a greaser from the '50's so likely will use graphite grease.

How does your living room Commando take a pounding? No never mind. I'm sorry I asked :D
 
Re: My swingarm bearings never leak oil – Something new to t

Yeah, bugs my wife no end too but her plants cushion the rougher crashes inside. I've a pair on the way to learn how to fit em and not mess the carpet.
 
Re: My swingarm bearings never leak oil – Something new to t

I may need those....gonna take my swing arm apart this week. I did make it home from the Gathering Ok.....Skip
 
Re: My swingarm bearings never leak oil – Something new to t

I would really like to try a pair of these - my 850 mkII is nearing completion, and I've been wondering about this very point.

Cheers,
Steve in Denmark
 
Re: My swingarm bearings never leak oil – Something new to t

Thanks for the great responses. Here are my instructions. It is a drop in replacement for the oilite bearing only using dry graphite as lube.

Installation instructions for graphite lined bearing replacement for the oilite swingarm bearings for my 1970 Norton Commando when I did my rebuild.
Things that you will need:
Appropriate Norton Workshop Manual (available on-line)
Set of ½ inch drive sockets
Fully threaded 3.5 inch long ½-20UNF bolt and nut
½ and 5/8 washers
Graphite powder
Large Hammer
Degreaser of your choice
Tape
New o-rings Norton 06-0448, 06-0449
Removal of the swingarm
1. Remove the rear wheel from the swingarm.
2. Remove the lower shock mounts from the swingarm and rotate the shocks out of your way and tie them up.
3. Remove the small bolt that holds the swingarm to the swingarm shaft. It is in the center of the swingarm under the horn. There is poor access to the bolt head so be patient. Later commandos have a different setup so check the workshop manual.
4. Remove the outer cover (locate the grease nipple) of the swingarm by unscrewing the long skinny bolt.
5. At this point nothing is holding the shaft in the swingarm but rust. It may take a lot of force to remove the shaft. Use the ½ fully threaded bolt and nut to make a jack to remove the shaft. The shaft has ½-20 threads. Use a socket that is bigger than the shaft on the inside hex and on the outside diameter that fits squarely on the shoulder of the swingarm. Fully thread the nut on the bolt and put the socket under the nut and tighten the bolted assembly to the swingarm until the bolt stops threading. Hold the bolt head and tighten the nut until it is flush against the socket and it will start to pull the shaft towards you when great resistance is felt.
6. Once the shaft is pulled out the swingarm is free to be removed. There is a cover on the other side that will fall out.
7. Remove the oillite bearings from each side of the swingarm using a press if you have one or insert a socket slightly smaller than the outer diameter of the bearing and hammer away with the back of the swingarm supported. The dust shields that are behind the bearing flange should fall out.
8. Totally degrease the swingarm, shaft, engine cradle hole and all parts to be replaced. This is important as the graphite is now your lubricant so dirty, oily parts are not desired. At this point, check your parts for looseness and corrosion. A rusty, pitted shaft or loose fitting shaft to engine cradle should be fixed at this time. The shaft should be a tight fit in the engine cradle. The swingarm bores might be a little rusty and require a light hone to clean up.
9. The new bearings should be a press fit to the swingarm. Stop if they are not. It should take a good bit of force to install. Install the graphite bearings from each side of the swingarm using a press if you have one or use the bolt, nut, and washers with a socket slightly smaller than the inner diameter as shown in the pictures below. Don’t forget the metal dust shields under the bearing.
10 Apply a dusting of graphite powder to the bearings. Apply a dusting of graphite powder to the shaft. Do a dry fit of the bearing and shaft. The new bearings will be a tight fit to the shaft but should rotate freely once dusted and installed.
11. Put new o-rings on the outer diameter of the bushings just like the old ones. Insert a new o-ring and tape the inner end cap in place. Replace the swingarm on the engine cradle. Align the shaft to pass through the swingarm and engine cradle. Insert the ½ diameter bolt to help align the shaft and rotate to get the small cross bolt to line up. After installing the cross bolt, check that the swingarm rotates freely.
12. Install the outer endcap with a new o-ring using the long screw. A ¼-20UNC set screw can be used to block access of the grease fitting hole or you can re-use the old grease fitting but just don’t ever grease it.
13. Re-install the shocks and rear wheel.
 
Re: My swingarm bearings never leak oil – Something new to t

Looks like a very nice mod, Baldy.

Slick
 
Re: My swingarm bearings never leak oil – Something new to t

dennisgb said:
How does your living room Commando take a pounding? No never mind. I'm sorry I asked :D

My swingarm bearings never leak oil – Something new to try (2014)


That's how!
 
Re: My swingarm bearings never leak oil – Something new to t

Baldy,

Great mod as well as a great post. Makes the forum seem relevant, once again.
 
Re: My swingarm bearings never leak oil – Something new to t

LOL, wife would shoot me in me sleep on our carpet but boy howdy I've done that inside mc shops full of cycles and people till too fogged to breath so we took it up again just outside door to finally pop tire and hear cheers from across hwy from onlookers grinning, once i could see past the smoke. I drew smiley faces and other designs with past Peel on our village square. I have Peel balanced on a wire frame milk crate and had to climb on dozens of times to fit cage and rear sets and bars but so far no topples but ain't run er up over imaginary idle sounds yet.

Anywho next to cracked crank cases and bent crank shaft, sprung swing arms are a sore point to me so need a success story to get over my early mechanical let downs on such a simple machine what could go wrong. I have seen DIY gusseted swing arms so apparently possible route.
 
Re: My swingarm bearings never leak oil – Something new to t

What is the difference between your $50 set and your $55 kit?
 
Re: My swingarm bearings never leak oil – Something new to t

I ordered a set. I would also be a player for the MKIII set I think.
 
Re: My swingarm bearings never leak oil – Something new to t

My plain pair arrived today looking like parts for a UFO scout ship. Very nice to handle til time comes to make fit Ms Peel. We need similar for the AMC sleeve bushes.
 
Re: My swingarm bearings never leak oil – Something new to t

Quaker city is making up a kit with the special bolt/nut and washers shown in the picture on the post. Also, graphite powder. That way, you can get prepared to do the install quicker.
 
Re: My swingarm bearings never leak oil – Something new to t

Baldy, what is the grey material in the bush reliefs for, porous sponge filler to hold oil or pre-lubed graphite desposits or what? Working up mood to diddle out old bushes til another custom dead end to seek outside shop help again. Btw burn outs are not very stressing to much but tire and air pollution but leaping off culverts into creek bed 3-4 ft down or encountering surprise tree across path no time to brake so must nail throttle to lighten front so rear smacks it and leaps over instead of nosing into it onto ground or hitting gopher holes in pasture and my favorite - rushing up couple story high 40' slope in yard to catch a few ft of air before touch downs bounce ups. All of this scares the poop out of me as ain't really good/practiced at it and do get tossed down or stuck too much but its what motivates me now I don't do gang drug deals or mess with married women any more as more trouble than worth the short thrills. I only want mud and straw under bike when parked at home inside.
 
Re: My swingarm bearings never leak oil – Something new to t

Hobot,

I am glad you are enjoying your new toys. The grooves and plugs are filled with graphite. As I recommended, you give it an initial dusting of graphite powder and get nice and slippy and then the grooves and plugs will continuously refresh the bearing with lubrication as it operates. Re-using the O-rings makes sure it is all sealed.

If you decide to add grease, this website indicates you won't have a problem. PM if you have any fitment issues.

http://www.spadone-bearings.com/graphit ... rings.html
 
Re: My swingarm bearings never leak oil – Something new to t

the shop is now showing out of stock for this - will you be making more sets?

Cheers,
Steve.
 
Re: My swingarm bearings never leak oil – Something new to t

Yeah man baldy I was initially depressed I'd made more work for myself but your bushes and depressions to hold graphite and oil are like jewerly to me to handle and view so how could I miss out as already run out of em this go around. Also I can't tell ya how transforming my cycle life and times in '04 became after pensively following the MX & trials riders into their element after they argued-warned me I should borrow an ATV or spare 2smoker, imply my heavy big twin was not up to it. Its been some years since I contacted Robert who alerted me there's a big element that loves the off road hazards more than the road racing like Ozark hwys. I assume I should soak the bushes in good synthetic oil then dust on graphite then wipe off and cap off. I now sure how to seal Ms Peel down there but sense I'll have Robert fab up something light and tight. Bushes in freezer so will let warm up in oil then freeze again and heat swing arm and hope I can suck em in with all threat rod. Suspect they'll last my life time. Besides handling heavy loads Peel should be pretty low maintenance.
 
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