SAE 90 vs 140 for swing arm spindle

Jonez69

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This has probably been asked many times before but it didn't really get directly answered in my search, so I'm asking. Is 140 absolutely necessary or can 90 be substituted? Would I get the same lubrication but need to add oil more often? Thanks for the replies!
 
This has probably been asked many times before but it didn't really get directly answered in my search, so I'm asking. Is 140 absolutely necessary or can 90 be substituted? Would I get the same lubrication but need to add oil more often? Thanks for the replies!
Lol, it all leaks out anyway. I have some Amsoil 140 left over from a previous vehicle. I figure I have a 300 year supply on hand.
 
I mix straight 40 engine oil with STP. Although the latest STP I bought is much thinner than it used to be so will probably just stick whatever the thickest oil is I've got in the swinging arm. Be aware that EP oil ratings are not equivalent to engine oil ratings. EP90 is a similar thickness to straight 50 engine oil.
 
I have filled 90 in mine. Usually Oilite bushings are impregnated with SAE30
Standard Oilite bearings are impregnated with highly refined mineral oil to ISO VG (SAE 30) having a high viscosity index and containing anti-oxidant, anti-rust and defoamant additives.
 
I soaked may bushes for a couple days and have them installed. I'm fitting the Kegler clamps today. I am going to use SAE 90 for now. Thanks again!
SAE 90 vs 140 for swing arm spindle
 
I just had a thought looking at the last photo.
If the centre locking bolt was hollow and a pipe attached to a clear plastic reservoir under the seat, the oil could be observed and topped up easily
Yes, my searches have come across that very idea, and it is mentioned in the article titled "Introduction to the World's straightest Commando" by Ken Augustine.
Unfortunately, my shop is not equipped to drill out a socket head screw to do the job. I'm working strictly with hand tools.
 
Dumb question but how does one administer such oil? I've been putting gear oil in a pump can and squirting/drizzling between the cracks next to the bushings. I was unsuccessful trying to remove the spindle in the fall so want to keep well lubed.
 
Dumb question but how does one administer such oil? I've been putting gear oil in a pump can and squirting/drizzling between the cracks next to the bushings. I was unsuccessful trying to remove the spindle in the fall so want to keep well lubed.
The early bikes had a Zirk fitting on there to administer the gear oil, the later bikes like mine 74 does not have such a fitting. I drilled a hole in mine, and ran a tiny rubber hose into it and have it zip tied up and out of the way. Makes it very convenient for me to lubricate the swing arm Whenever I choose to.
 
The early bikes had a Zirk fitting on there to administer the gear oil, the later bikes like mine 74 does not have such a fitting. I drilled a hole in mine, and ran a tiny rubber hose into it and have it zip tied up and out of the way. Makes it very convenient for me to lubricate the swing arm Whenever I choose to.
This is what I've done to my 75 , with the Welsh caps . Later 74 's used permanent Welsh caps too . The manual says sealed for life , no maintenance needed . That was 51 years ago , so keep it lubed . Thick oil .
 
This is what I've done to my 75 , with the Welsh caps . Later 74 's used permanent Welsh caps too . The manual says sealed for life , no maintenance needed . That was 51 years ago , so keep it lubed . Thick oil .
The mk3's have felt oil absorbing material stuffed in spindle ends, loaded with oil, then a different seal design than mk2 amd permanent welch caps/plugs. So they are considered no maintenance.

An easy option on the mk2 with oiler zerk...drill out or replace zerk with a drilled oit one...fit a length of clear tygon tube to the oiler, add your oil to tube, cap with a suitable bolt and zip tie tube end somewhat above the spindle....easy to keep and eye on level and add as desired.
 
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This has probably been asked many times before but it didn't really get directly answered in my search, so I'm asking. Is 140 absolutely necessary or can 90 be substituted? Would I get the same lubrication but need to add oil more often? Thanks for the replies!
Penrite do a 140 gear oil, it's blue. Nice as.
 
The mk3's have felt oil absorbing material stuffed in spindle ends, loaded with oil, then a different seal design than mk2 amd permanent welch caps/plugs. So they are considered no maintenance.

An easy option on the mk2 with oiler zerk...drill out or replace zerk with a drilled oit one...fit a length of clear tygon tube to the oiler, add your oil to tube, cap with a suitable bolt and zip tie tube end somewhat above the spindle....easy to keep and eye on level and add as desired.
That's what I have done
I have a small master cylinder resovoir under my seat to refill it
 
Same here. Regarding 140w oil, if you can't get it, EP90 will do, or even engine oil, any oil is better than no oil. I use Shell Omala 320 g/box oil as that is what we used in the crushing mills g/boxes at work.
I have come to the same conclusion that SAE 80w-90 gear box oil will do the job. I have plenty of that on hand and if SAE 140 can be substituted with another number , why buy it. Having just recently becoming a Norton owner ,this is the 3rd 850 Commando I have owned in the past couple of years. My suspicion is that most owners over the years have taken to using a grease, rather than an oil on these spindles. This 1974 is the first of my Nortons that I have gone through, and indeed, the spindle was packed full of thick grease and so was getting no lubricant whatsoever. My red 73' 850 is probably filled with grease as well, but until it comes apart, I won't know positively. I did "top it off" with 80-90 gear oil last year but have no idea if it is getting to the bushes or not. Thanks to all, the forum is a great tool to keep these old machines going!
 
Dumb question but how does one administer such oil? I've been putting gear oil in a pump can and squirting/drizzling between the cracks next to the bushings. I was unsuccessful trying to remove the spindle in the fall so want to keep well lubed.
Assuming you have the spindle with the long/thin through bolt...

Correct: Oil Nipple on the right side of the spindle. Easy: Through the center bolt in the cradle that screws into the spindle.

If your o-rings are good, you're doing nothing or almost nothing.
 
I have come to the same conclusion that SAE 80w-90 gear box oil will do the job. I have plenty of that on hand and if SAE 140 can be substituted with another number , why buy it. Having just recently becoming a Norton owner ,this is the 3rd 850 Commando I have owned in the past couple of years. My suspicion is that most owners over the years have taken to using a grease, rather than an oil on these spindles. This 1974 is the first of my Nortons that I have gone through, and indeed, the spindle was packed full of thick grease and so was getting no lubricant whatsoever. My red 73' 850 is probably filled with grease as well, but until it comes apart, I won't know positively. I did "top it off" with 80-90 gear oil last year but have no idea if it is getting to the bushes or not. Thanks to all, the forum is a great tool to keep these old machines going!
IMHO, the "correct" oil for the bushings is SAE30 but that is very likely to leak so Norton specified 140. Almost any plain dino oil will work, just the tinner it is the more likely it is to leak. 80W90 has chemicals added to change the viscosity. I would no use that nor would I use engine oil 20W50. SAE40 would be find, IMHO

I use 140.

Grease destroys the bushings and spindle. I've taken apart quite a few where it all had to be replaced.
 
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