Slippage in gears 1 - 7

[bike_the_planet]

Hi Folks,

The missus and I have just completed a 4 month tour of Europe; me on an original Nomad and her on a Club Tour. Both bikes were retro-fitted with Rohloffs before we left. Both frames had modified l.h. rear dropouts to facilitate the fitting of the OEM Ex Box. However, because they are not capable of taking EBBs, each were fitted with a chain tensioner.

Following the first oil change immediatetly before our tour started, the hubs behaved almost faultlessly over 4000 kms plus.

We're currently in the UK, but whilst riding some hills yesterday my 3rd and 4th gears started slipping. I immediately sought flatter ground and managed to get back to base before any more dramas. My immediate suspicion was the chain tensioner. However, subsequent investigation on a further ride today has revealed that gear 1 - 7 are all slipping violently, to the point where my legs and the crank will skip through a half turn suddenly. However, try as I may, I cannot get gears 8 and above to slip.

I have loosened the cable adjusters to ensure that the changer isn't trying to disengage the gears but to no avail. Watching my chain whilst this slippage happens definitely does not show any sign of the chain jumping/derrailing. The slippage definitely appears to be within the hub itself although there is no diificulty in selecting gears using the changer.

My suspicion is now directed at the reduction gear in the hub. I believe that the Rohloffs are a 7 speed box with a reduction gear to give the 14 speeds.

I will be dismantling the bike shortly before transport back to our home in Perth, Australia. I plan to drain the hub beforehand and refill with oil when we arrive home. If that does not cure this, then it sounds like a 'back to Rohloff' job.

Needless to say I'm extremely relieved that this didn't happen during our tour - it would have really taken the shine off things.

Has anyone else experienced anything like this? Any thoughts?

Looking through other postings I note that most cases of slippage are due to the use of the chain tensioner - this does not appear to be the case here. There is also some info regarding slippage in gears 3 and 4 requiring re-shimming. May be this is similar.

Any thoughts/suggestions gratefully received.

Kind regards,

Tony (of Perth but presently shivvering in the UK)

[freddered]

Call SJSC immediately

[stutho]

Tony

The are two small springs just underneath the left axle plate if these are missing or damaged then you will see exactly the symptoms you described.  I have also read a mail where the Axel plate was loose that coursed the same issues.  If you are using the Threaded axle version (as opposed to the quick release) then also check you haven't overtightened the axle bolts (max tension is 35NM) 

Let us know what the outcome is


StuTho

PS if you are currently near  Swansea / Gower  (South Wales) then my door is open!

[bike_the_planet]

Thanks for your suggestion, StuTho, I will have a look this afternoon.

Not 10 mins beofre the gears started to slip I was crawling up a 1 in 4 in 1st without any problems whatsoever, so maybe something is loose.

Currently in hilly Gloucestershire, so 7 speeds only is a bit restricting. But we are flying home this wednesday.

Cheers,

[stutho]

You probably know this but if you are going to tighten (or remove) the axle plate you are going to need a Torx key -TX20.

StuTho

[bike_the_planet]

StuTho,

I have a Thorn multitool that includes a tx20 drive. I noticed that the Ex box axle plate is not loose.

If i remove the 5? tx20 bolts holding the plate on is there anything I can check underneath? In other words, are there any springs that may pop out unexpectantly??

Cheers,

tony

[stutho]

Tony,

First note that I don't own a EX box both my hubs are internal models.  However...

Are you using the Quick release version (CC) or the Threaded axle version (TS)  If it is the TS version I would first try just refitting the wheel.  I have problems myself when the Axle nuts are over-tightened.  It may be possible to over-tighten a Quick release as well?

On to the Axle plate.  If you are going to remove it first draw a little diagram of the alignments. Be careful  when removing not to damage the two paper gaskets.  The springs shouldn't jump out at you! But if you remove them note which holes they go in.  Also make sure the Wheel is lying on it RHS otherwise you WILL have an oil leak.  On reassembly you should but a drop or two of blue threadlock on the axle plate screws but in the short term this wont matter. 

The Rohloff manuals can be downloaded here http://www.rohloff.de/en/download/description/index.html

Best of luck

StuTho

[stutho]

Forgot to say that the springs in question are behind the external transfer box as well. 

[bike_the_planet]

Thanks again StuTho,

I have checked the two springs behind the axle plate and they seem ok.

Obviously you were on the money with this suggestion as Rohloff Australia (on advice from Germany) recommended the same approach.

I have asked Rohloff to send two new springs to me anyway. I will replace them and do a full oil change. If that doesn't fix it, then it sounds like a return job. I hope it doesn't come to that though.

Regards,

Tony

[stutho]

Did the oil change do the trick?

If you are yet to do it can I suggest that after you add the flush go out for a ride (say 10 miles) before you drain out the gunk and put fresh oil in.  This will give the flush a proper chance to work.  I realise that for the ride you will have limited gears but keep trying the lower range.  The springs mentioned above push on 2 pawls my guess (now) is that one or both is gummed up somehow.

Stutho

[bike_the_planet]

Hi StuTho,

Sorry for the delay in replying. Am still in the process of organising a new internet account.

The hub didn't respond to new springs or an oil change. I have therefore had to return the rear wheel to Rohloff. A bit disappointing, but it seems to be a rare occurance. It maybe that persistent flushing might have helped as your theory about being gummed up is what I suspected as well. I would be very surprised if it was as the result of any mechanical failure, but all will be revealed when the unit is returned.

In my jet-lagged state I sent the hub road instead of air. As Rohloff are in Brisbane and I am in Perth, this may take a couple of weeks.

Thanks for your suggestions,

Cheers,

Tony

[bike_the_planet]

For those interested in the development of this fault, I have just heard from Rohloff that the reason for the slippage was due to a small quantity of sealant on one of the five bolts that secure the axle plate.

When I questioned Rohloff Australia as to what they meant by 'sealant', Mrs Rohloff, who is german I believe, best translated it as Loctite. She said it was making contact with the freewheel ring.

She assures me that the problem is now solved, though I'm still waiting for the hub. However, the service manual states that a small amount thread lock should be used to ensure they don't free up during riding. So how much is enough, but not too much?

When I removed the screws for inspection just after the fault first manifested itself, I could see little trace of Loctite on the the threads, but noting exceptional on any of them.

I must say that this all sounds a little tenuous.

Does anyone know what clearance there is between the bolt end when fully tightened and the freewheel ring. Could this be the cause?

And why would it suddenly start slipping after 7000 kms of trouble free riding???

Whilst I acknowledge that the Rohloff is a good product, I would be hesitant touring on it again without knowing exactly why this would suddenly happen.

In the meanwhile I have been using derailleurs again.They have their shortcomings as we all know. But in 30 years I've never had to put a bike off the road for more than a day to fix the problem or buy a new part.

I'm pretty unimpressed

Cheers

[bobs]

I have been thinking about selling my Sherpa and getting something with a Rolhoff gears. After reading this and seeing the spare parts list on the SJSC website I'm having second thoughts. I know normal gears are not perfect but at least most people can fix then and get spare parts. Is a Rolhoff worth the cost if you are not doing mega miles.

[stutho]

bike_the_planet

I am a bit perplexed by this explanation.  I am wondering if there has being something lost in translation? 

I have just gone and read through in detail the current version of the manual.  One thing that I did notice was that the recommended tightening torque on the 5/6 bolts that attach the axle ring and plate is actually quite low - 3NM.   The other thing I notice is that the current manual never say to use sealant on the bolts - except in the in one of the appendixes  in relation to oil leaks.  I have a very bad memory but I could of sworn that the thread lock information used to be more prominent - I am wondering if there best practice has changed?

[ians]

Is a Rolhoff worth the cost if you are not doing mega miles.

it all depends on what you include in 'cost'.  I don't do mega miles or expeditions to the back of beyond.  I commute, go out for day rides and do the very odd bit of credit card touring on my Raven Sport Tour.  The Rohloff has two advantages for me; (i) hills.  I can get up hills easier and faster than I ever could on my Super Galaxy. I put this down to the linear gear system.  No switching back and forth between granny rings. (ii) I've done no maintenance yet in 18 months.  I have to clear the grot out of my wife's derailleur gears almost every week in winter.

We took our MTBs to Spain in the summer.  I sold my frame when I came back and bought a Sterling Frame and Rohloff/rear wheel.  I'd rather spend time riding my bike(s) than cleaning them.

If you just do the sums on price then Rohloff will always be more expensive if you don't do a high mileage.  If you include your time then it alters the balance (in my view).

And don't forget - most people post to forums when they have a problem.  There must be lots of very happy Rohloff owners out there that you never hear from.  Except me perhaps.

ians.