Intro, oil leaks, and sprocket chainlines

[mickeg]

Oh ... is that stuff called oil?  I thought, that when it was out of a Rohloff, it was "nectar of the gods". Proof of heaven. 

Nectar of the gods is what came in the containers shown.

[TheShipwright]

ARGH!!!! I was finalising the the setup of my bike by carry out an oil change and changing the rear sprocket and I damaged the "drive unit" or "driver" (sorry I forget teh exact name), it's the part the sprocket removal tool connects to. The sprocket was REALLY difficult to remove and I had a few attempts at it and think I must not have tightened it enough on one occassion. Possibly a combination of tight sprocket and my poor method.

I've sent it off to SJS after talking to Dave their Rohloff chap and whilst chatting it over I mentioned my potential "oil leaks" and he said "I wouldn't be overly concerned about those, it's not uncommon". As it's now going in for work I'm getting a full service (new gaskets I think are included) and the new sprocket style carrier installed.

I "may" have over reacted and panicked with my decision regarding changing to the new style sprocket carrier but I assume I can always remove it and go back to a traditional styel screw on.

FYI Dave said turn around is circa 3 days for a full rebuild at present so let's hope the Parcelforce get a move!
Cheers

[mickeg]

...
I "may" have over reacted and panicked with my decision regarding changing to the new style sprocket carrier but I assume I can always remove it and go back to a traditional styel screw on.
...

Apparently the thread on sprockets will no longer be made, only the new style.  For chainline reasons, I want to stay with the old style, I recently bought a spare thread on one.  Many of my miles are on derailleur bikes, plus I don't put on the high mileages that some people do.  Thus, I think I have a lifetime supply of oil and sprockets.

If you might be able to use your old one in the future, make sure you tell the shop that you want that part returned.  Most shops discard old parts.

I found it pretty easy to get my sprocket off after three years.  I only took it off just to make sure I could get it off, not for some other reason.  The key is a good size chain whip and long wrench.  And a good coating of grease on the threads when you put it back on.  Or, if you have a monstrous vice bolted to a robust work bench, maybe the wrench is not that critical, but I prefer a really big wrench over the vice.

[TheShipwright]

I read about the threaded batch but I'm guessing it only matters to peopl running chaincases and who are wedded to 54mm chainlines.

I'm going plop some spacers on chainring and maybe budge my EBB over a bit as well.

Regarding the return of the old sprocket, I've put it on the note that i attached to the wheel so hopefully it will come back.

My sprocket I think was stuck fast, I suspect that previous owner and previous previous owner had both tried and given up as it was quite worn.

thanks for the info
gerry

[geocycle]

ARGH!!!! I was finalising the the setup of my bike by carry out an oil change and changing the rear sprocket and I damaged the "drive unit" or "driver" (sorry I forget teh exact name), it's the part the sprocket removal tool connects to. The sprocket was REALLY difficult to remove and I had a few attempts at it and think I must not have tightened it enough on one occassion. Possibly a combination of tight sprocket and my poor method.

I "may" have over reacted and panicked with my decision regarding changing to the new style sprocket carrier but I assume I can always remove it and go back to a traditional styel screw on.

FYI Dave said turn around is circa 3 days for a full rebuild at present so let's hope the Parcelforce get a move!
Cheers

Your in good company, I did exactly the same and my hub is also currently with sjs. I've replaced the sprocket several times but this time it stuck fast and the rohloff tool slipped damaging the driver. On Dave's suggestion I'm going splined. I'll report back next week after a bike less week in Provence!

[Danneaux]

I am surprised that Dan has no oil film on his skewer, as I assumed an oil film on the skewer is normal. 

Hi mickeg!

Sorry for the delay, I was away.

I just removed my skewer and here is how my hub looks. The skewer is not totally dry...wiping the full length of the shaft did produce a little "color" on the ridges of the paper towel, but not enough to soak in. No oil has leaked from the axle nor onto the adjusters. My external shift-box is pumped full of Phil Waterproof Grease, and this has not migrated either.

I hope the pictures are helpful

Has more oil migrated from your hub since tightening the screws?

All the best,

Dan.

[mickeg]

...
I just removed my skewer and here is how my hub looks. The skewer is not totally dry...wiping the full length of the shaft did produce a little "color" on the ridges of the paper towel, but not enough to soak in. No oil has leaked from the axle nor onto the adjusters. My external shift-box is pumped full of Phil Waterproof Grease, and this has not migrated either.
...
Has more oil migrated from your hub since tightening the screws?
...

It is clear that my hub loses a lot more oil than Dans. 

And to reiterate from before, I use the 15ml theory instead of the full 25ml at oil change time.  So, am not really overfilling it.

I have not ridden my Rohloff bike since I posted my last comment above with the skewer wipedown, I regularly ride about four or five bikes a year and have been riding my Sherpa for the last several weeks.  I will ride the Rohloff bike on Thursday as I will want to use the dynohub powered light to light up a long tunnel on that day.  But my tightening of the screws was so minimal, that I would be quite surprised if that makes things tighter.  They were already quite tight, so each screw was turned maybe only a few degrees.

There are a couple paper thin gaskets on that side of the hub, I might take a look at them next time I have the wheel out of the hub.  I will probably be putting on studded tires in Nov or Dec, so will likely have the wheel out in a few months if not before.  I just hope I do not damage any gaskets in the process.

[TheShipwright]

Dave (the Rohloff man at SJS) has just phoned me to say that my hub has been repaired and is on it's way back to me (hoorah). All gaskets have been replaced (along with with my new style sprocket carrier and new sprocket) so when it's back and being used I'll report on any "misting/leaking" etc.

Big thumbs up from SJS and specifically Dave re the speed of service and their customer service.

Dave also reported that the internals of the hubs also looked in good condition, which is re-assuring as I'm never likely to see the inside of the hub!

Also I rang back to ask Dave about adding chainring spacers and I got Andy on the phone. Andy's opinion was not to worry about the spacers to bring it out to 57-58mm just run it at 54mm.

[mickeg]

...
Also I rang back to ask Dave about adding chainring spacers and I got Andy on the phone. Andy's opinion was not to worry about the spacers to bring it out to 57-58mm just run it at 54mm.

I wanted a narrower Q factor than a perfect chainline would have produced.  Thus, I bought a bottom bracket spindle that is about 10mm shorter than a perfect chainline would have dictated, that means my chianline is intentionally off by 5mm.  So I am pleased to hear that Dave thinks small error is unimportant.

But I did not want my chainline error to grow from 5mm to 8 or 9mm with the new system, so I bought a spare thread on sprocket while they are still available.

[TheShipwright]

very wise mickeg!
I now have 4 of them as I had planned to do my ration experimentation with the screw on version, hence my comment upthread about "panicking" and getting the new style sprocket carrier installed maybe a bit too quickly.

What do people think the consequences of having the chainline out by 3/4 mm will be?
Noise and premature wear?

Thanks

[mickeg]

...
What do people think the consequences of having the chainline out by 3/4 mm will be?
Noise and premature wear?

Thanks

By 3/4mm do you mean three quarters of a mm or do you mean 3 to 4mm?

I did chainline calculations for my chainline before I bought the bottom bracket for my Nomad.  If I was going to worry about 5mm chainline error, I would have bought the right spindle length bottom bracket, but I felt that a 5mm chainline error would not be noticeable.  Think about it, most derailleur bikes have more than a 5mm chainline error most of the time.

If I have any excess noise from that or excess wear, I have not noticed it.

A local charity received a bunch of new KMC chains from a major bike manufacturer.  These chains had been installed but were removed from bikes that had defective frames.  The charity sold them for $5 USD.  I bought several.  It will be several years before I worry about chain wear.

[martinf]

What do people think the consequences of having the chainline out by 3/4 mm will be?

I try and get chainline about right, but have sometimes run hub-gear bikes with up to at least 8 mm off the chainline without noticing any ill effects.

As Mickeg says, chainline is much worse a lot of the time on derailleur bikes. I suspect having enough slack in the chain is even more important if the chainline isn't spot on, and it might be better to use a flexible derailleur chain rather than one of the specific hub-gear chains. That said, I was using 1/8" specific hub-gear chains.

Chainline might be more important if using a Chainglider like I do now on 3 of my hub-gear bikes, but for me the main issue with the Rohloff splined sprocket carrier is that it probably puts the sprocket too close to the seatstay to fit a Chainglider without modification. 

So like some others I have bought 3 spare screw-on sprockets, which should be enough for at least 30,000 kms of riding, probably much more.

[geocycle]

I have now gone splined!

My chain had run out of adjustment and the new chain would not run smoothly on the worn teeth so I needed to reverse my sprocket.  I've done this lots of times before but this time the rohloff tool slipped and damaged the 'driver' in the hub (the part where the tool sits).  I clearly didn't tighten the skewer that retains the rohloff tool enough.  So, SJS replaced the driver for me and we agreed to change to the new splined system. The results are below, hope these help envisage what the change involves.  Ignore the scratches on the hub (an unfortunate incident with barbed wire!)


It does sit a few mm further out from the hub (see side profile).  There is clearance in my RST frame but it is relatively tight.  Note, I wasn't able to run a chainglider properly before the change and there definitely would not be room now.

It runs fine and I cannot see any significant difference in the chain line.  Overall, I'm happy that the next change will be easier!

[TheShipwright]

Thanks Geocycle.
I too have had my hub back but due to a little postal hishap I haven't actually used the hub yet as I need a new OEM2 axle plate.

That's a good idea adding some snaps for others so here is my recently mounted (but unused hub) with the new carrier style sprocket.  Regarding chainline, I couldn't resist making some spacers for my chainring at the front to move the chainring out a bit further, probably because I couldn't ride it and wanted to tinker!

I calculated that the centre of the new sprocket was 9.5mm from the inside my 135mm spaced dropouts, resulting in a 58mm chainline, which conventiently coincided nicely with the thickness of the alu I used to craft my chainring spacers.

Edit: I've measured properly now and it is actually 10.5mm from inside the dropout meaning that it is a 57mm chainline.

Enough wittering here's my snaps in case they help others.

[mickeg]

Thanks for the photos.