Rohloff freewheeling problem

[Jorn]

I bought my Raven Tour with a Rohloff speedhub this summer before starting a bicycle trip from North Cape, Norway to Cape Agulhas, South Africa. Im currently in Addis Ababa, Ethiopia and have the Nubian dessert in Sudan, some 2200 kilometers ago, experienced problems with the rohloff gears. The problem is a big hassle since Im far away from home (and any roholoff servicecenters), and I would therefore very much appreciate any piece of advice about what to do.

The gears are freewheeling (as I guess is the proper word when the gears are "jumping", making the pedal turn about 120 degrees without any resistance) in #14 #12 #9 #6 #5 & #3. This limitation of gears has been especially annoying in the many hills of Ethiopia!

In Karthoum I changed the oil. My sprocket was in addition worn and (since I had already reversed it) I changed it, hoping this would make things better (and I have always made sure that the the chain is properly tensioned), but without any luck.

The intensity of the freewheeling varies but is severe. In the worst gears ie. #5 the freewheeling occurs every 300 meter or so.

Any ideas anyone?

[stutho]

Jorn,

This sound pretty serious!  Have you contacted Thorn / SJS Cycles?  They may be able to arrange something for you.

Tel           +44 1278 441 500
Email    thorn@sjscycles.com


There are three things you might like to try - although it sound to me as if the hub need professional attention!

1. (Especially reliant to the TS version of the HUB) Try loosening off the Axle nuts (or quick release) a bit - Apparently if you over torque the Axle nuts you can cause a problem similar to what you are seeing

2. Loosen off the shifter cables a bit - I have personal experienced this one.

3. Try thinning out the oil a bit in the hub - by adding say 10ml of Rohloff change assistant fluid to the hub - I think this is the LEAST likely to work in your case, as the daytime temperature  is going to be pretty high - and therefore the viscosity of the oil low anyway.

As I said I think your hub is going to need  professional attention.

As I understand it there is a known issue where new hubs sometimes require to be re shimmed after they have bedded in. This may well be  your issue.  It effects less than 1% of new hubs and normally shows up in the first 2000km- as the hub beds in.  After re shimming the hubs are apparently good  for another 100,000km+

Let us know the outcome

STUTHO
   

[Blacksail]

Hi, I experienced similar problem a week or so after an oil change, hub would freewheel in various gears until a new gear was selected. I bled some air out of the hub and problem went away. Hub had done 6,000km before the problem occurred and has done another 10,000km since without a further slip.

Hopefully you have a syringe handy as it is a quick and easy fix if this is indeed the problem.

Goodluck

[stutho]

Blacksail,

That is very interesting.  The hub is 'meant' to breath into the middle of the axle on the CC version (quick release) or into the right hand stud on the TS version (nutted).  So I presume in your case the hole has / had become blocked and this condition resulted.   Which version of the hub are you using?

stutho