Alfine 8 - improved sealing..?

[John_S]

Hi Brucey,

Many thanks for your reply/advice because this is really going to help me with lots of food for thought whilst thinking about my next bike.

Cheers,

John

[Suffolker]

I have a total of 8 machines equipped with assorted SA and Shimano hub gears. It would in theory be economical for me to use the Castrol Spheerol FG-00-EP semi-liquid grease that @Brucey mentions earlier in this thread.

There's one problem, which is that the smallest quantity I can find on the internet is 12.5 kgs at about £100 plus. That would probably last me 30 or 40 years which, as I'm in my 7th decade, is a little unnecessary. Does anyone know (or can point me to) a source of this grease in a smaller quantity?

The other alternative NLGI-00 grease available in a small amount seems to be Penrite, which comes in 500ml size. However, it is described as "soap thickened", which is less desirable than the Spheerol. Would it do if I cannot obtain the Spheerol?

[Brucey]

There's one problem, which is that the smallest quantity I can find on the internet is 12.5 kgs at about £100 plus. That would probably last me 30 or 40 years which, as I'm in my 7th decade, is a little unnecessary.

-whither optimism....?

OK you have a few options:

1) buy a different SFG. You can buy a nice SFG meant for installation into land rover front swivels. This is good stuff and it is not expensive if you buy it from an independent LR parts supplier. It is chock full of EP additives and solid lubricants, and whatever remains on the swivel parts as they move stops the exposed parts of the spherical joints from corroding nicely, so I think it should resist water ingress in an IGH OK.

2) DIY lubricant manufacture. If you take readily available Castrol LM and mix it with gear oil you will make something that will be an approximation to the spheerol. It will take some experimentation to get the right mixture.

3) just use gear oil. Most (but not all) SA hubs have a lip and will hold a teaspoonful inside (provided you seal the ring bearing screw threads with PTFE tape if necessary) and Alfine/Nexus hubs are also reasonably oil-tight provided the RH seal is fitted correctly. Hubs without a decent RH seal and without an inner lip of any kind (eg most older SRAM designs) just leak oil out as soon as it is added; these hubs need to be greased.

BTW most greases are 'soap thickened'; this is quite normal. If you look up the data sheet it may (for example) say 'xxx.stearate' by which they mean a soap, whose sole function is as a thickening agent.

BTW of the lubes above the land rover grease is probably the best. The gear oil/SA/spheerol are all a good lubes but will not protect the parts quite as well at the lowest speeds and highest loads IMHO.

If you do use gear oil, use a synthetic gear oil if you have a choice.

Do be cautious if you are mixing different greases; in some cases the soaps will react with one another and this can cause the grease to turn to something that looks more like putty. Thus if lubing a hub that was originally greased, it is a good idea to flush it out first. If you can't be bothered to dismantle the hub to do this, flushing it (in use) with an excess of oil will usually work OK.

BTW in A8 and N8 hubs the RH hub bearing (under the sprocket) won't see any fresh lube unless you either add it (e.g. by partially dismantling the RH side of the hub - which needs some measure of caution-) or being sure to use a very mobile lube inside the hub. The shimano procedure is pretty much ineffective in this regard.

cheers

[Suffolker]

Thanks for that (as usual) very informative reply. Stacks of things to think about and get cracking on.

I think I'll get hold of some of the Land Rover grease, and have a go with that, to begin with. As I also have a lot of Castrol LM, I should then be able to use the LR grease as a comparison for some DIY mixing. I also have a large amount of Dow-Corning Molykote grease, which is pale yellow and quite soft. This came from the now-defunct UK factory of a Japanese TV maker,and the label is all Japanese. I don't know whether it went into the sets, or the manufacturing machinery, but I'll see whether this might be made to serve in some way.

Thanks again.

[mjr]

Can Shimano hubs be lubed through the hole where the shifter rod goes like SA ones, or is tapping a lube port essential? Certainly something grey and greasy seems to coat the shifter rod of my N3.

[rofan]

Can Shimano hubs be lubed through the hole where the shifter rod goes like SA ones,

N3 yes (oil)
N4/7/8 A8/11 no (without shifter rod)

[mjr]

OK, thanks. I hadn't realised how different the shifting was! http://sheldonbrown.com/nexus-mech.html#joint

[Brucey]

word of warning; the N3 RH cover is a hard plastic part which is a snap fit onto the hubshell. If you oil this hub, the oil escapes PDQ, because there is no internal lip on the hubshell and the RH cover is not oiltight.

N4 RH seals vary but most are not oiltight either.

Some (certainly the current) versions of the N8 and N7 hubs have a three-part RH cover, which comprises a rubber lip seal onto the driver, a hard plastic shell, and a rubber insert to make the seal onto the hubshell near the ring bearing. This seal type ought to be more or less oil-tight.

As a general rule if you add oil and it comes out, add SFG instead; probably this won't leak out so quickly, and the flushing action of the oil will lessen the chance of a reaction between the greases.

cheers

[bobc]

Land rover swivel hub SF grease - great idea, thanks Brucey

[mig]

question...when a new hub is sold to the end user is it supposed to be maintained by them after a given period? or somewhere in the accompanying paperwork does it state "return to shimano approved service engineer after xx months, maybe sooner if subject to wet conditions" etc?

[Brucey]

from this Nexus SI techdoc http://bike.shimano.com/media/techdocs/content/cycle/SI/Nexus/InternalHub/SG8R31_36/37J0A-001_SG-8R31_36-EN_v1_m56577569830638076.pdf

-In order to maintain proper performance, it is recommended that you ask
the place where you purchased the bicycle or your nearest Pro shop to
carry out maintenance such as greasing the internal hub about once
every two years starting from the first time of use (or once about every
5,000 km if the bicycle is used very frequently). Furthermore, it is
recommended that you use the Shimano internal hub grease or
lubrication kit when carrying out maintenance. If the special grease or
lubrication kit is not used, problems may occur such as the gear shifting
not working correctly.

-The internal hub is not completely waterproof. Avoid using the hub in
places where water might get inside it and do not use high-pressure
water to clean the hub, otherwise the internal mechanism may rust....

- Parts are not guaranteed against natural wear or deterioration resulting
from normal use...

So they are saying service it every two years... unless, that is, you actually use your bike (3000 miles/5000km is both too far IMHO and anyway soon achieved if commuting), and even then they are saying that 'if you use your hub where water might get inside it' then all bets (and possibly the warranty) are off.... er, does that include... rain...?

Well, I know of enough of these hubs that have clapped out through being used 'normally' in 'normal British weather' that I wouldn't choose to use one in the most foul winter commuting use unless the lube in the hub is improved (in both quality and quantity) and the service interval shortened to one year or less.

In some countries the N8 hub acquired an extremely bad reputation early on because nearly all of the hubs failed in the first winter.
eg see post from 'interestedcp' here http://forum.ctc.org.uk/viewtopic.php?f=5&t=64432&p=814639

Revised seal designs have certainly helped but the problem (on N8 and by extension A8) is not entirely solved. The N7 -imperfect though it is in some other ways- appears to be more reliable than the N8, possibly because the airspace inside it is simply smaller (the N7 internal is pretty chokka with parts inside; the N8 has much more fresh air within...) . Also the N7 is more likely to be fitted to bikes with long mudguards, good chaincases, skirt guards etc, and that helps keep the weather out because the vulnerable driver area is covered on the right and the roller brake covers the left side. In several LBS near me they don't bother to service N7 hubs on such bikes, because they view it as being a waste of time; the chances are that the hub will last ten years on a sit-up-and-beg bike with a chaincase etc anyway. Maybe such bikes don't do as many miles, but it seems a fair bet....

cheers

[mig]

would you be able to estimate how much more $ it would take to design and produce this same hub that has both good seals and simple access for the right grease/SFG/oil? i wouldn't think that it would be much more?

[Brucey]

it would cost about 20p to add a lube port in the factory, and less than that to add a vent in the hubshell/axle that wouldn't suck water into the hub due to the airspace effect.

From shimano's perspective the oil port would be a mixed blessing; they may view it as encouraging users to put any old thing, in any quantity into their hubs... which they would (naively in many cases IMHO) assume to be a problem within the warranty period.

Their warranty period is two years.... so in theory you should have a hub service just before the warranty expires even if you don't need it through use or mileage. By then however it is too late (way too late) for a proportion of hubs.

If they understood the true conditions of use properly, they wouldn't use the designs and lubricants that they do use; they are wholly inadequate for the task in hand.

cheers

[boblo]

Presumably if you leave your lube port unsealed it'll stop the hub sucking moisture in as it won't be able to create a vacuum? Bit like the lube ports on old Campag hubs?

[Brucey]

yeah, but if the lube port is put in the obvious place, all the lube will come out if it isn't sealed there. Because of all the steel parts fitted to the inside of the hubshell, there are not too many places where the lube port can be fitted.

This hub (ignore the other stuff bolted onto it)



has the lube port in the same place that I have added them myself; 5mm either way and you would hit hardened steel on the inside of the hubshell.

BTW this page (posted by a Seattle bike shop)
http://www.rideyourbike.com/shimanoIGH.shtml

shows some Nexus and Alfine hubs that 'have seen a bit of weather'; the weather in Seattle isn't so much different to that in parts of the UK. The conclusions are similar to my own, in terms of what you need to do to keep these hubs running OK in these conditions.

cheers