okane

I know this has been asked so many times I hesitated to even post this, but I just haven’t been able to determine a consensus of opinions so here goes.

I have a nos 74 date AW SA hub purchased from a LBS that closed its doors 2 years ago.

Had it laced to a 27” alloy wheel and it shifts nicely (haven’t ridden it yet…just tested on the stand) but it certainly needs some oil in that it appears almost empty.

First question is, what is the capacity of these hubs? I hate oil leaks from overfill.

Secondly, I have on hand 20wt motor oil, automatic transmission fluid, and lots of Tri-flow I purchased at a ridiculously low price from the aforementioned bike shop.

I have looked all over the net and opinions vary wildly. I’m very hesitant to use the ATF for fear of what it might do to the rims. The 20wt I’ve have in an unopened can that I’ve had for years. I’d like to use the Tri-flow but some say it is too light and will leak.

What is the current consensus here? Thanks for your opinion

easyupbug 

I will be interested in the responses as I have not touched one of these in 40 years, nor have I ever re-built one or had a NOS hub, but back in the day we used a little 20wt when available of 30wt if not. I agree with avoiding ATF & way too thin Tri-flow. So can't help with volume for first charge but for maintenance we used very little, just a squirt (technical term), much less than an oz.

JohnDThompson 

You don't need to fill the hub shell with oil; about a teaspoon (5cc) initially, and a few drops every few weeks to replace what leaks out.

You can use ordinary motor oil (20W is recommended), but ideally a detergent-free oil should be used. The detergent in typical motor oils can absorb water, which in a hot engine will be boiled off in use, but in a bicycle hub just sits there and can lead to rust.

okane

RE the capacity, even if the hub is almost or near empty, just a teaspoon? The oil I have does indicate detergent, but one location in my searches throughout the net indicated detergent is good because i suspends impurities and keeps parts clean....no my conclusion just what I read.

Moe Zhoost

Agree with the others. Just a bit of oil is needed. Just enough to coat the surface of the internal parts. Seepage will lubricate the outer bearings but this should not result in oil migrating down to your rims unless you overdo it.

JohnDThompson 

Yes, it just needs to coat the internals, not flood them. Riding will distribute the oil pretty evenly.

The detergent in motor oil serves to dissolve water that condenses in the engine as it cools and would otherwise collect in a pool at the bottom of the oil pan. Engine heat will boil the water out in use.

leob1

Leaking from overfill is the least of you worries. It's a British product, so oil leaking should be expected.

Use the 20w.

HillRider

Former Triumph or BSA owner?

okane

Having owned 7 MG As, 3 Bs, and 2 Sprigettes I know all about oil likes and the Prince of Darkness which is why I would like to keep the leaks to a bare minimum.

AnkleWork

A few answers here:
https://www.bikeforums.net/bicycle-m...my-sa-hub.html
HTH

Really, use the Tri-Flow. The solvents are very good for bearings and gears.

okane

Thanks for all the replies. Due to some serious health issues I had put the bike aside and forgot that I posed this question previously.

Feeling a bit better now and the consensus seems to be 20wt, so that's what I will go with.

Again, thanks for your imput.

tcs

Gold medal - NLGI #00 semi-fluid grease in the mechanism; soap-based water-proof grease in the axle bearings and labyrinth seals.



Silver medal - GL4 75W90 Gear Oil


Bronze medal - 20~30 wt motor oil

WizardOfBoz

Sheldon Brown has a page on servicing these hubs. He recommends "about two teaspoonfuls of a good quality thin oil".

https://sheldonbrown.com/sturmey-archer/aw.html

also

https://sheldonbrown.com/sturmey-archer_tech.html

and for oil type ("Use machine oil, not a spray lube or other thin oil. Unless a hub has sealed bearings, also use grease, to form a seal at the bearings and help keep the oil in." here:

https://sheldonbrown.com/internal-ge...ml#lubrication

dedhed

I certainly wouldn't be running either of those lubes if I thought I might be riding in temperatures under 50 F.

I run 10-30 full synthetic motor oil in a S-5 without issue.

tcs

That's cool. Like Brother Dave said, 'Everybody's got their own kick going.'

As I'm sure dedhed knows but some of you might not, 75W-90 gear oil has the same range of viscosity as 10-W40 motor oil.




Additionally, as explained very well by poster brucey over on the CTC forum, gear oil is made for splash oiling at ambient temperatures, unlike motor oil which is optimized for pressured oiling at elevated temperatures. Quality gear oil formulations "contain additives that help with 'stringing' or 'climb' characteristics; this means that in (say) a gear train, the oil is lifted and transferred to other parts far more rapidly than if the additive wasn't present. You don't need much of this to happen before the gearbox is adequately lubricated whilst in use".

Tribology science marches on, and NLGI #00 semi-fluid grease is, of course, the lubricant the Sturmey-Archer factories have used for the last thirty years or so. Back to brucey: "SFGs have a cunning characteristic; a few minutes after being worked, they are thick enough to hold their own weight (more or less) so cling well to all surfaces inside a hub, and aren't likely to leak out. However when being worked, they 'shear-thin' enough that they behave more or less like oil, i.e. the lubricant can climb, splash, and penetrate where it needs to go to.

"This means that a hub lubricated with this kind of SFG will enjoy many of the advantages of a hub that is lubricated with oil, but will have a far lower leak rate, and can sustain an increased fill too; this means longer service intervals and better protection for the parts too. Once some hubs are 'run in' I'd expect them to go for several years and/or a five-figure mileage on a fill of SFG. This is only possible with oil lubrication if the sealing is 'perfect', and even then there won't be as much oil inside the hub, so any wear debris will be a greater part of the whole."

Back in the day, Sturmey-Archer offered their own oil. It seems to have been an old-time additive-free motor oil of ~20wt. Traditionalists can use my third suggestion, 3-in-One Motor Oil (NOT 3-in-One Multipurpose Oil).

WizardOfBoz

Interesting post, tcs. The other characteristic in motor oils is that they have detergents. Detergents are meant to keep dirt, crud, and metal particles in suspension. In a car, that's great: the oil is continuously filtered and so the dirt is removed and the oil lubing the engine parts is clean. Not sure if this extends to bikes, but one doesn't use motor oil in machine tool (lathes, milling machines, saws, presses and the like) gearboxes because there usually is no circulating system and no filter. In such a gearbox, you want the dirt to settle on the bottom of the gearbox and stay there, out of circulation.

Seems to me, though, that if SA uses and recommends that NLGI semifluid grease, that might be the ticket. That said, a light machine oil probably would lube as well (but you'd have to replace leaked oil a bit more frequently.)

One last point is viscosity variation with temperature. Straight-weight motor oils (SAE 30W, for example) meet a viscosity specification for a single (typically high) temperature. In vehicles that operate in varying climates, you'd have to change to thicker (higher "weight") oils in the summer, to maintain lubricity, and a lower weight oil in the winter to allow your oil pump to get the oil circulated. Multi-weight (or more correctly, multi-viscosity) oils are designed to meet two viscosity specs. These are specified with two numbers, such as 10W30. One number specs viscosity at cold temperatures (that's the 10 part of 10W30), and the other for high temps (obviously, that's the 30 part). Since an IGH hub is not going to get to the temperature of an internal combustion engine, the first number is more important.

But I suspect that you shouldn't be using motor oil. Use machine oil without detergents!

tcs

These little guys are pretty robust and tolerant. Back in the 1940s & into the 1950s, when the UK was recovering from the big war, times were tight and many products were rationed or unavailable. Sturmey's official maintenance manual from those days suggested that if 'proper' lubricants were unavailable, the cyclist could lubricate the mech with sewing machine oil and - you might want to sit down for this - pack the axle bearings and labyrinth seals with Vaseline!

dedhed

[QUOTE=tcs;21198466]That's cool. Like Brother Dave said, 'Everybody's got their own kick going.'

As I'm sure dedhed knows but some of you might not, 75W-90 gear oil has the same range of viscosity as 10-W40 motor oil[QUOTE]

I just know that trying to squeeze 75/90 EP gear oil into my leaky NP 205 Xfer case South of 40-50 degrees is work. Granted I'm tryong to push a much larger quantity than needed for a SA hub. Maybe next season I'll try the 75-90 on the old Sprite and see how it works.

The 00 grease is commonly used for vintage leaky steering boxes and gear cases on things like brush hogs as it doesn't leak out as fast. Some guys (in warmer climates) will even go to 0 "corn head grease"

GamblerGORD53

I have taken my 2 SA hubs apart a dozen times and have ZERO clue about WTH a labyrinth seal is.... ?? Pffft

Mine have synthetic Crazy grease on the bearings. The oil is 10w30 non-detergent stiffened with 1/4 Wynn's old motor additive. They wander together so I have to watch what oozes towards the drum brake chamber. Other than that and what I wipe from the indicator chain when it's apart, I see NO need to replenish the oil. It barely gets dirty even after 4,000 miles. As for miniscule wear on the inside planet cogs, the black coating is a bit worn away. I have done several 125 mile rides and 45 mph downhills with the RD-5w, so I certainly don't baby the thing. But then, I rarely get it caught in the rain like commuters.

WizardOfBoz

It's simple a groove (the labyrinth cavity) is on one part into which a disk (the labyrinth blade) attached to the other part protrudes. Often used (with many cavities and blades, as shown) in very high-tech compressors, sometimes with the labyrinth being pressurized, and multiple stages. It can give a good seal with little friction.

In a bicycle, its likely a single groove with a single blade. Because of this you can fill it with grease to make a better seal, without adding too much friction.

tcs

The late Jobst Brandt explained in his always gentle, fatherly way:
https://yarchive.net/bike/labyrinth_seals.html

okane

20 wt has been installed. Didn't notice any change as it was perfect on the stand already. Test ride will come when we have a decent day and my back (spinal stenosis---some days good, others torture) permit.

elcraft

Some say that checking that the oil filler port is not facing down when parked will reduce some seepage. Additionally, synthetic grease in the main bearings is less likely to be flushed out from any oil seepage. And obviously, not laying that bike on its side will also prevent oil from seeping out of the aforementioned "labyrinth" seals. These hubs, w/ a teaspoon of oil inside, are virtually indestructible.

Dan Burkhart 

I've had a few NOS Sturmey Archer hubs pass through my hands, and all showed signs that they had been packaged with no lube in the internals.
This example is a 1983 model that showed enough corrosion to be a concern.
That said, I always open and inspect NOS hubs before putting them in service.

dmark 

+1