Lubricant for S.A. 3 speed hub?

[Golflad]

What is the preferred lubricant for the 3 speed hub. Mine has a lovely cap to open; what shall I use?

[mjr]

Thickish oil (if you don't mind the leaks) or Landrover front CV joint grease IIRC.

[[XAP]Bob]

Brucey's special sauce....

[robc02]

SA used to (maybe still do) sell their own oil for the purpose. A lot of people reckoned SAE30 lawnmower oil was an equivalent. There may well be better options but these have kept many hubs going for decades!

[ket]

What was Brucey's special sauce?

[atoz]

I use Wilkinsons very cheap "oils well" comes in small plastic container with spout. Not as thick as motor oil but seems to work well. People seem to think that traditional motor oil (for old type vehicles) works well also. Whatever you do, avoid Three in One oil.

My "shopping trolley" bike has an AW hub dating from 1968- was salvaged by an old acquaintance of my late father who used to tinker with old bikes- this was salvaged from a tip. Just needed a new pawl, and also a longer axle so it could be used in a more modern frame, back in 1986. With a 24 tooth sprocket and 48T chainweel you get approx 40, 53 and 70 inch gears- quite adequate for shopping and canal towpaths. It will probably outlast me!

The modern SA hubs don't have the oil hole with plastic cap mine does. You have to unscrew the toggle chain and tip on one side to pour in. The really old ones (like my Dads) had a nipple lined with rubber for an oil can with injector- dead loss- the later plastic cap was a good move- so why did they get rid of it? I know in theory the new ones are packed with grease, but those hubs are really designed to use oil, little and often- a case of "if it works, don't fix it"- doh. Still at least they're still being made. Pity they don't do the 4 speed FW/FM or the medium ratio 3 speed AM any more..but that's history. Mind you, the 5 speed was not a success, and I bet no-one misses it.

Saw a Youtube video about someone taking part a Shimano Nexus 7 or 8 speed hub. Looked a lot more complex than my AW..

[Mick F]

I used to put 3in1 in mine. Lasted for decades with zero maintenance other than a squirt or two every month or two.

These days, my SA is "sealed" (ha ha) with no means of lubing unless you devise a good method of getting it in. I have thought of fitting my own lube port like they had in the old days. Not got round to it yet, but I may do soon perhaps.

[Golflad]

Thanks for that. I was going to put EP Gear Oil in!! Engine oil it is then. My Honda uses 10-30 visc. That should be ok.

[Brucey]

almost anything is better than nothing, and these gears usually last for decades with regular doses of pretty much any oil inside, even something that is almost completely unsuitable.

However as a lubricant, EP gear oil is vastly more suitable than any engine oil, and any engine oil is likely to be a major step up on 3-in-1.

if you want to lubricate at less frequent intervals, a fairly runny (think the consistency of tomato ketchup) semi-fluid grease (SFG) with solid lubricants, corrosion inhibitors and EP additives will give the best protection and lubrication for your hub. [ Anything thicker than that and it can interfere with the action of spring loaded pawls, if it is used in anything other than fairly sparing quantities; modern SA hubs come lubricated sparingly with a grease that is thick enough that it doesn't move around much inside the hub.]

If you want to buy something 'off the shelf' then the SFG that is used in land-rover front swivel hubs is pretty good. This is used as a 'one shot' treatment to replace EP90 gear oil.

cheers

[rjb]

I lubed my hub with a 50/50 mix of Mobilux Ep3 and an ep90 gear oil. It made a nice thixotropic consistency. No thought, it was what I had to hand. I did notice that the hub was then very draggy for a hundred miles or so but then freed up. Anyone else had this experience.
And I now seal my hubs using PTFE tape when I replace the innerds and a waterproof grease in the left ball race, and also a thin ring of silicone under the thin steel cover behind the sprocket. This has reduced leakage to almost negligible.

[Brucey]

the lubricant needs to be both correctly thixotropic and pseudoplastic if there is not to be excessive drag when there is plenty of lube present.

I have heard of NIG three-speeds which are correctly adjusted but don't freewheel 'normally' because they have too much thick lube in them; what happens is that the ball ring drags the ring gear around with it, and forces the planet cage to rotate too. If set in top gear, there is a loud clunking sound as the sliding clutch is overrun and the toggle chain can be seen spasming.

If there is just too much lube you can also get a phenomenon known as 'churning' going on. In this mode the grease swirls around and there is quite a lot of work put into it. In high speed applications churning can cause serious problems. In bicycle parts it normally adds a bit of parasitic drag and tends to push excess lube out of the way; either elsewhere inside the housing or out of the housing altogether.

cheers

[rjb]

That explains it. I had got into the habit of putting into neutral when descending as that made a big difference. I will see if I can drain some out by leaving the filling cap open with a container below overnight. It's a dynohub so some lub may have migrated into the dynamo. Hope this doesn't cause any issues, overheating possibly is an issue.

[Brucey]

I don't think you need to worry about overheating or damage to the generator; the usual problem is corrosion inside.

FWIW lubricant drag between the ring gear and the ball ring is mainly noticeable when freewheeling. The only time these parts are moving relative to one another is when freewheeling/backpedalling and when pedalling in low gear. If you want to reduce this drag you can increase the internal clearance of the hub slightly by adjusting the RH cone 1/4 turn further out; in an old AW based dynohub (an AG) then it will still work Ok with the RH cone backed out 3/4 of a turn, it'll just rattle a bit when there is no lube inside it.

In an AG there isn't much unused space inside; it would be easy to have a bit too much lube.

cheers

[Mick F]

If you want to reduce this drag you can increase the internal clearance of the hub slightly by adjusting the RH cone 1/4 turn further out ..............

Would that not make the wheel bearings too loose?

Don't you want to adjust bearings to the sweet spot, or does that not matter on these hubs?

[Brucey]

If you want to reduce this drag you can increase the internal clearance of the hub slightly by adjusting the RH cone 1/4 turn further out ..............

Would that not make the wheel bearings too loose?

not unless you do that and nothing else.

You set the internal clearance in the hub on the RHS and then set the other cone to suit it. BTW you can't check how the internal clearance is set properly without backing the LH cone off first.

cheers