Earl Grey

When I stripped down my Brompton (part curiosity, part service) I switched my SA 3-speed to motor oil in the internals, grease in the bearings. It leaks constantly. I'm tired of having to clean the rim every other ride (under 20 miles) to keep the rear brake working and quiet (not to mention the dirt it attracts on the hub shell, spokes etc).

Is this just a normal rate of leakage for modern SA? I thought I was pretty sparing in the amount of oil I put in (a couple of ml or approximately half a teaspoon), but I do have the bike on its side quite frequently as it goes in checked baggage, which maybe makes escape via the bearings more likely.

Because it wicks everywhere and is thrown around it's really hard to see where the leak is occurring; past the main axle bearings or via capillary action through the ball cup / ball ring (only the right side has ever been removed, the left side is pressed in).

If this is par for the SA course I'm just going to call my experiment a failure, strip it again and return to the light grease throughout that it came with from the factory.

fietsbob

I use Phil Wood tenacious oil.. it's a bit sticky.. seepage is what lubricates the Axle bearings.. [BSR]

some dirt sticking to the Hubshell.. havent really wiped it clean in several Years ( do a more vigorous cleaning when I replace the Chain.)

my Mk 2 I got used , I did a grease the axle bearings on that one as It was over 10 years old when I bought it. (so inspected the cones)

Earl Grey

Yeah, I suspect the Mobil 1 that I used is a lot lighter than Tenacious (I have Mobil grease in the axle bearings, so I'm not depending on the oil for that). If it was just the hubshell getting dirty I'd be OK with it, but it's constantly all over the spokes and rim.

wschruba

20wt SAE oil is too light, if your goal is to keep the oil in the hub. In the time of coaster brakes, it didn't matter, since the oil didn't impact your brake, so they used what they had.

Without seeing how much you greased the outer bearings, I can't comment on how resistant to leaking the hub would be--but, you have to really pack the grease in, and have a, more or less, unbroken surface over the bearings. Capillary action will still pull oil out past the minute gap that is created by spinning members. Speaking of grease, you should be using a marine grease, if your goal is to keep stuff in/out.

My experience is that SA hubs get an oily sheen on them over their service period, no matter how hard you try to keep the oil in the hub...it just wasn't designed for it.

fietsbob

Oh well.. part of the issue is rim size S-A 3 speed lube oil was 3-in-1 light, but the EA3 rims of classic 3 speeds were Larger, so further from the Hub

but 349 rim is closer to the hub..

My Go To Bearing Grease, for decades, has been Marine .. Boat Trailer Wheel Bearing grease.

Wilfred Laurier

SA hubs eventually leak every drop of oil applied to them. They have no 'seals' whatsoever. The solution to this is two-fold - (1) add a little oil into the oil port every few months... the argument above about the specific viscosity is totally overthinking it - just any old oil will work, (2) install a leather strap loosely around the hub body to catch the oil and keep the hub clean... this was very common when SA hubs were king.

San Rensho 

Everything British leaks oil like seive. If you ever had a norton or an mg there was always oil leaking evefywhere. If it stopped leaking oil it meant you were out of oil!

The old joke was a guy buys a brand new mg in the 60s. He takes the car back to the dealer and tells him there must be something wrong with the car its leaking a pint of oil a month. The dealer says yes there is problem. It should be leaking at least a quart a month.

fietsbob

Then there is all the Lucas Electrical Jokes that are favored by British Vehicle owners .. 2 & 4 wheel ( 3 if you include Reliants.)

Why is British Beer served at room temperature ? ..... Lucas refrigeration.




BTW, no oil port in the hub shell Any More.. remove the indicator chain that shifts the gears, the Hollow axle is your oil Port.

San Rensho 

Lucas - Prince of Darkness - Lucas Electrical Humor Jokes

Earl Grey

Thanks for all the input.

Good point about the diameter, Bob - less rim to spread the escaping oil out over, higher RPM to sling it, and less spoke to traverse to get there. Probably makes a difference.

I am pretty sure the axle bearings got a sufficiently heavy application of grease (my approach is "use a lot and what it doesn't need will leave shortly") but I'll take a close look at the condition when I pull it. I still wonder if the bike spending hours on its side has contributed to washout / breakdown.

No one seems to think this exceptionally unusual, so I guess I'm going back to the #00 grease (internals) and #2 grease (bearings) SA now use as standard. Thanks again.

Dan Burkhart 

Lucas is an acronym for Loose Unsoldered Connections and Splices

rhenning

The old joke about the question of "When to I add oil to a SA hub? The answer of course is "When it stops leaking out." Roger

Scooby214

I ended up going back with 00 grease in my Sturmey. I really don't detect any increased drag while riding it, even in winter, and the wheel stays much cleaner.