Initial oil fill

[buffet]

My hub is coming unfilled (as all hubs which re not installed on a bike), what is the best amount for the initial fill? Should I go for something lower than 25ml, say 15ml?

[Andre Jute]

My hub is coming unfilled (as all hubs which re not installed on a bike), what is the best amount for the initial fill? Should I go for something lower than 25ml, say 15ml?

In theory your new, "unfilled" uninstalled hub actually has 12ml or more of oil in it, enough to coat all the mating surfaces. Again, in theory, that is the condition it would be in after a year of use, just before you service it, however much oil your put in at the beginning of the year. Once more, the whole chorus now, in theory you could therefore ride it for a year without doing any damage.

I might even ride a well-run-in Rohloff box on trust without adding extra oil, if it arrived from some some notoriously reliable chain flosser, say Dan the Mod.

But a brand new Rohloff box is a piece of German agricultural equipment. Those gears are going to grind off tiny slivers -- and you want enough oil to carry them away from mating surfaces.

The safe course is therefore to drain the new hub -- take the grub screw out, let the hub stand hole down over a bottle of suitable size for a couple of hours and see if anything drips out.

If no oil whatsoever comes out, fill with 25ml of Rohloff's All Seasons oil.

If a drop or a few of clean oil comes out, there's oil clinging to the surfaces and you can fill with 14ml (my choice, others pick nearby volumes) and ride the bike. The 14ml of oil is to carry the evidence of work off the gear surfaces and away from the axle bearings

***
At least once before the first routine scheduled service at 3000m/5000km, probably at a 1000km or a 1000m, you should give the box a full service according to the manual instructions, to remove any possible metal grindings. This can be the last time you put in the full 25ml of All Seasons Oil. The purpose is still to carry away the filings to the space at the bottom of hub.

***
At your next service at 3000m/5000km, you can be certain that enough oil sticks to the gears, so you can from then on fill with 14 or 15ml or whatever you decide on that is convenient to measure.

***
The service kits with two bottles for cleaning and running oil and a syringe and a new screw stud are useful. You should buy two sets to have the tools, and then you can buy the bulk 250ml cans of cleaning and running oil, which are much more convenient.

Good luck with your bike.

[buffet]

Thanks, Andre! I'll see if I can drain anything from the new hub.

[Oswestry Ken]

Hi Andre, I've just covered 660 miles on my new Mercury. Are you saying I should do its first oil change around now just to get rid of metal shavings, etc?
Or, am I OK to wait until the first scheduled oil change at 3000 miles?

[JohnR]

At least once before the first routine scheduled service at 3000m/5000km, probably at a 1000km or a 1000m, you should give the box a full service according to the manual instructions, to remove any possible metal grindings. This can be the last time you put in the full 25ml of All Seasons Oil. The purpose is still to carry away the filings to the space at the bottom of hub.

Your comment prompted me to do an oil change in my Mercury which has now travelled 2300 miles. On intial draining over at least an hour the hub produced about 10ml of dark grey oil with a silvery glint - more like metal dust than pieces of metal. I then put in about 10ml of flushing oil and turned the pedals in gears 3 and 5 for a few minutes before doing another oil drain but this time only about 5ml came out but I waited less than 1/2 hour. I then added 5ml of new oil. I'm not worried if it's diluted by some flushing oil as thinner oil is more appropriate for the winter and will do another oil change when spring has arrived.

[buffet]

John, how much oil was in your hub to begin with, 25ml?

[JohnR]

John, how much oil was in your hub to begin with, 25ml?

The bike came from Thorn and I've read somewhere that they reckon 15ml is sufficient. However, if I managed to get 10ml (approx) out then it was probably filled with Rohloff's recommended 25ml as some oil has probably disappeared during use and some will have stayed on the gears. The temperature (about 5C) was sub-optimum for getting maximum oil drain. I consider this to be an interim oil change and reckon that what's now in the hub will be sufficent until I do a more thorough oil change in the spring.

If you haven't read this document http://www.sjscycles.com/thornpdf/ThornLivingWithARohloff.pdf then do so. Page 32 relates to oil changes.

[Andre Jute]

Hi Andre, I've just covered 660 miles on my new Mercury. Are you saying I should do its first oil change around now just to get rid of metal shavings, etc?
Or, am I OK to wait until the first scheduled oil change at 3000 miles?

Now is a good time to do an oil change. There's zero point in being economical about a few quid's worth of oil if it makes your very expensive hub gearbox last long enough to be passed on to your grandchildren.

JohnR in his post immediately above this one mentions glints of metal in the oil he drained. Under a microscope that "powdery" stuff will appear pretty sharp-edged.

 If you want to see what your gearbox is excreting, put a magnet in the oil you drain before you throw it away.

[Oswestry Ken]

Thanks, Andre. I did ring Thorn and they said there was no real need to do so but I think I'm with you - no harm in doing an early oil change and maybe it will do a bit of good.

[PH]

I bought a new hub earlier in the year and did the first oil change at 2,000 km, I've since done another 3,000km and will change in January, then revert to every 5,000 km or 12 moths (It's likely to be the former with this bike)
Does it need it?  Probably not, but a couple of early changes used to be common practice with all straight cut gears, it's a simple job, cheap enough if you bulk buy the oil and IMO can't do any harm.

[JohnR]

Your comment prompted me to do an oil change in my Mercury which has now travelled 2300 miles. On intial draining over at least an hour the hub produced about 10ml of dark grey oil with a silvery glint - more like metal dust than pieces of metal. I then put in about 10ml of flushing oil and turned the pedals in gears 3 and 5 for a few minutes before doing another oil drain but this time only about 5ml came out but I waited less than 1/2 hour. I then added 5ml of new oil. I'm not worried if it's diluted by some flushing oil as thinner oil is more appropriate for the winter and will do another oil change when spring has arrived.

I can add that the hub seems to be better after the oil change. Overall gear shifting feels slightly easier and the occasional mis-fires when changing into 11th gear and ending up somewhere else appear to have gone away.