Speedhub freewheel failure?

[Chris S]

Greetings, it feels like the freewheel is slipping on my 500/14 Speedhub. It does it in all gears under load and is worse (ie: now unrideable) since I fitted a new chain to see if that was the problem. The sprockets are a little worn but it’s not the chain.

I’ve only done about 2000 easy/light km in 2 years on this hub fitted on a Cannondale running 34/13 with tensioner.
The unit was bought used in 2006 but was less than a year old and has worked fine till now. I admit I have never changed the oil but can't see 2 years of light use wearing out a Rohloff freewheel.

I’ve looked on Rolhoff’s troubleshooting webpage and have searched the internet and this forum and - oddly - there is no mention of this particular failure. But what else could it be?

Thanks for any ideas.

Chris S

[geocycle]

Sounds like one for Rohloff but here are two thoughts, are the hub seals touching the sprocket, or could the problem be with the chain tension ie is the tensioning arm too slack?  I doubt it is an oil change issue although this will not do any harm.

I saw the following on the rohloff site:

11.07.2005 On bikes with a chain tensioner, the chain springs off the sprockets
Chain tensioner runs dry and turns with difficulty
Grease the chain tensioner or replace the jockey wheels, see Owners Manual "Service" 2. or "Repairs" 2.

Chain tensioner spring is defect
Replace the chain tensioner spring, see Owners Manual "Repairs" 2. Check the chain length on full suspension bikes, see Owners Manual "Mounting" 5.3.1


No chain guide in use
Mount a chain guide, see Owners Manual "Mounting" 5.4
All bikes fitted with a chain tensioner need to be fitted with a chain guide (eg Rohloff chain guide CC Art.No. 8290). This prevents the chain from springing off the chainring.

[stutho]

Hi Chris,
Can I just confirm that you are getting free spinning in all gears?

My initial thought was that the one or both freewheeling springs had being removed (it is very easy to do this by accidently) but having checked on the Rohloff site this will only affect gears 1 to 7. 

Given that you don't know the history of the hub I would give it an oil change PDQ.  The previous owner may of used the wrong oil - or not realised that the hub ships dry!  Whatever the case an oil change is always the fist thing to try - new oil can only be a bonus.  When you do the oil change filter the oil that comes out to see if you can see any metal fragment in there.

Let us all know how you get on.  This is the first time (on this list) that anyone has reported an totally failed speedhub. I (for one) am very interested in the outcome.

Stutho

[Chris S]

Thanks for your replies and ideas. I can't get on this forum most of the time ('data error').

The Man from Rohloff said it could not slip in all gears so must be chain slip.
I got someone to film the hub/chain jumping while pedaling uphill and then played it back in slow motion. I still could not see the chain jump but assumed that must be it.

It was not free-spinning in all gears, but jumping, eventually on the lightest loads. The fact that I have moved to a very hilly area and was riding a lot may have brought it on.

My bike runs 13T with a tensioner (converted by my LBS - tensioner tension is still fine) and now I see that with this arrangement only about 4-5 teeth are taking the strain rather than 6-7 if the chain wrapped fully round the sprok in a no-tensioner set up. So that may explain premature wear of the sprocket. I've never worn a sprocket out before on a bicycle before and to me it looked OK. As we known Rohloff say 13T is the smallest and bigger sproks are better.

So I've now gone to 17T plus whatever up front to maintain the 19-100 inch set up which suited me before. I may even try to eliminate the tensioner if by some fluke the new chain length lines up with the drop outs.

fyi, getting the sprocket off: maybe everyone knows this but the Rohloff manual's suggestion of cranking a 24mm spanner on the sprocket tool against a chain whip didn't work for me (again I think the small sprok diameter didnt help, even with a set of handlebars on the end of the whip). I think sjs suggest clamping the hub/tool in a vice; in my case it just bent the cheapo whip but a couple of blows with a hammer and chisel on the sprok and it was off. fyi2: the threads are 'normal' ('righty tighty; lefty loosey').

Also, when it comes to putting a new sprok on, the shallow threads make it easy to cross-thread if you're gagging to get the bike on the road again. I slowed down long enough to learn to push the sprocket onto the hub prior to commencing screwing and then turn the hub to make sure new sprok is lined up and turning flat too, not at an angle. At this point it screws on smoothly. Apologies if I am stating the achingly obvious.

Haven't put it all together yet (answering on this forum while I can) but if it all works out fine I'll take it out and treat it to a candle-lit oil change.


Ch

[stutho]

Reading both your emails I would still say the most probable candidate was missing or faulty pawl springs.  Are you sure that the original springs are still in place and that the previous owned didn't try to  'Upgrade' them?  Bad pawl spring should only effect gears 8 to 14 but.... It is certainly the place I would start. 

You REALLY need to do the OIL CHANGE as well. If the oil in the hub is too thick / emulsified  it might be gumming up the pawls (unlikely but worth the expense of an oil change)

I haven't run a 13T Sprocket and I don't run a tensioner.  But I can tell you my 17T has  10 to 11 thousand miles on it - it is still on it's first side and still looks in very good condition (much better than my aluminium chain ring!) bigger sprockets are defiantly better  both in terms of sprocket life and chain life (I am still on my first chain as well)

The Rohloff Speedhub will eat all but the best chain whips.  I  snaped a cheapo on the first try, I replaced it with a decent whip that lasted a while and then also snapped. I don't own one but I would recommend a Park SR-2 not cheap but should last.

Best of luck