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Discussion Starter #1
I had a rohloff hub in a gary fisher rig and its worked flawlessly for the couple of years that I've ran it. My LBS has now moved the rohloff over from my rig into a surly pugsley. Since the switch the hubs gears seem to slip a lot. Sometimes they just won't engage and sometimes I'll be pedalling along and the gear will disengage. Please can anyone give me some suggestions for things that my LBS can try to resolve the problem so that I can advise them ( they have no experience with rohloffs .)
The shop have changed the oil with proper rohloff oil
They have changed all of the gear cables with new rohloff ones
They have really tensioned the chain.

Any advice
Thanks
 

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I'm going to bet money that you're missing one or both of these springs, and that they fell out when you bike shop adjusted the external shifter box orientation to fit the new frame. I bought a "broken" Speedhub for a song (+ shipping) and all it needed were these two little guys. Without them, the hub freewheels a lot, sort of like you're describing.

 

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I agree with Speedhub Nate, although I believe to further narrow it down, if you were missing either or both of those freewheel springs, you would only experience the problem in gears 1 thru 7. Here is the backside of Nate's picture:

Another thing I would look into is cable tension. It has been noted that too-tight of shift cables will allow the hub to "half-shift", or slight hand movements on the shifter during riding will be just enough to initiate a half-shift. Your twist grip shifter should have a moderate amount of play, and your cables entering the shift box should not feel snug either.

When removing the wheel from the bike, can you give the sprocket a quick turn by hand, and does it rotate freely, albeit for a short time?

Also of interest might be a couple Youtube clips I made when I took apart my hub a couple months ago:
Strip:
https://www.youtube.com/user/climbercraig66#p/a/u/1/lS6kj8g5On8
Build:
https://www.youtube.com/user/climbercraig66#p/a/u/0/Y-1iPbYra58
 

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Discussion Starter #4
Thanks for the replies. The hub does not only slip in gears 1 - 7, it definately slips in 13th and 14th gear.
Any other thoughts?
 

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I am assuming it is a QR axle? I know Rohloff says that some of the bolt-on axles, if overtightened will cause bad shifts. Worth a try to back-off the QR tension.

Being that the hub worked fine for years, I am leaning in the direction of the install to the new bike being the culprit. Rohloff usually says that most hub malfunctions will occur early in the hubs life, and if you have made it past that point, you should be OK.

So how about some more specifics?

Mileage?
QR or threaded axle?
What gears specifically does it slip in?
Any specific situations? Does it only happen while climbing?

If it is only gears 13-14, I'd venture to say that one of the gear cables was cut too short and might be limiting the shift axle travel.

I know I have a heck of a time getting the cables set just right before trimming them to the right length.

And what does "They have really tensioned the chain" mean? Too much chain tension is bad news for everything drive-related, including the Rohloffs driver bearings.

First thing, and easiest to try, is you should remove the wheel, feel the sprockets rotational tightness, and whack the axle with a rubber mallet. This will ensure that everything is seated correctly, and may correct an alignment or axial distance problem.
Here is a better picture detailing the process;

 

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Discussion Starter #6
It is a QR and I think that it is really tight. The shop originally fit the hub without chain tugs and so tightened the QR really tight. The bike now has chain tugs so could be slacker on the QR. They did tighten the chain really tight to stop the gears slipping, I didn't think this would make any difference and it never.
I don't know exactly which gears slip it seems random but definately 13 and 14. It's not only when climbing or under pressure, it will slip just when making a basic change with no pressure.
It will slip whilst pedalling, and when trying to change gear as well quite random.
I would say that on a 20 mile night ride on thursday it probably slipped about 20 times and I learned to avoid 13 and 14.
I am never stranded, I just can't always have the exact gear I want.
If you lift the rear wheel from the floor it is a little stiff to pedal the cranks around and the wheel dosen't seem to freewheel as long as it should.
Thanks again
 

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Being that you describe it as being so widespread across all gears, I'd again lean towards something system-wide than just one thing not working right. Keep at it.

I would recommend (in this order) these top 3 things to look at:

1. Axle clamping tension = Ease up a bit. Loosen your chain while you're at it.
2. Attempt the mallet smacking technique, as detailed in the Rohloff illustration I posted.
3. Reinspect your shift cable for excess tension. Consider running new cables, and take care to do it exactly as listed in the instruction manual.

And, try each one of these things seperately, so if it starts working right, you know what was wrong.
 

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Discussion Starter #8
Thanks very much, I'll forward this to my LBS to run through.
Really appreciate it and I'm sure the shop will too.
If I get to the bottom of this I'll add to this post to give you the verdict
Thanks again
 

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Another thing that I just thought of, is that Rohloff is very explicit about not disturbing the alignment of the gear that connects directly to the shifting shaft. So this theory plays off Nate's idea that, maybe the gear mech was removed or otherwise disturbed, and now all of your gear changes are screwed up due to that. In the manual, it says "5 out of 6 potential positions are not correct", meaning that there is alot of opportunity to screw this up. =)
Good news is that it is easy enough to check. I scanned some images that you can take to the bike shop with you:


 

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Discussion Starter #11
You are a true gent. Surely one of these will sort the job. you've been more helpful than the uk rohloff guy I've spoken to. I'll let you know how it pans out.
Cheers
 

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No problem! Having a non-functional Rohloff is unacceptable!

Hopefully the big-wigs at Rohloff stumble upon this message and propose that I serve as a Rohloff mechanic for the Americas and Canada. Working on Rohloffs (and getting paid)from the comfort of my garage would just about qualify for "dream-job" status.

But realistically, I guess it would be pretty slow business.

Anyway, hope one of those suggestions gets you sorted out. Looking forward to hearing your resolution.
 

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Thanks alot for this thread. I lost gears 3, 5,6, 12, 13 and 14 very suddenly for no apparent reason. My hub had done just over 5k and had had its first oil change about 2 months ago. It was running fine then lost those gears. The thing that fixed it was the rubber mallet. All good now and in fact the pedals that used to turn when the bike was walked have stopped turning. So I guess it was a running in thing Thanks for your detailed advice.
 

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No other changes.I used the rohloff oil change kit and followed the instructions. I used all the oil in the plastic container they provided which I believed was the correct amount.
 

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Hmm, sorry none of those ideas worked out. Well, there goes my dream job!

So you say you did the mallet smack technique, and things were fine? For how many miles? Interesting that it seemed to work, and then quit working again.

And I can't think of any rhyme or reason for your particular gear slips i.e.

If gear 3 slips, so should gear 10
5 and 12 match up
as do
6 and 13
But, if 14 slips, so should 7
And if the Hi/Lo clutch engagements are holding fine for gears 1, 2, 4, 7 LOW and 8, 9, 10, 11 HIGH....... Then I am confused.

But hey, I will keep thinking about it, looking for a common link. In the meantime, good luck.
 

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It worked OK for about 5k. At one stage I had no gears at all. I tried the hammer again and it worked for about 10 meters. I will check again which gears it is and update.
 
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