sprocket reversing problem anyone?

[daviddd55]

£80 !!! Did I miss something?  Did he throw in a new wheel or something?  That's the same cost as a new sprocket, removal tool, new chainwhip, new vice and a few beers to celebrate completing the task

no that's correct Freddered - is that that expensive? I expected to pay more for Rohloff stuff, and even more in Oz, and he did spend 2 hours fitting it (and a broken chain whip and nearly broke his back in the process!!!). I've no idea what UK prices are like for Rohloff stuff.

[stutho]

Freddered:

If the sprocket spins off anti-clockwise, what stops it from spinning off under load from the pedals?

Um the chain pressure will tighten the sprocket.  If you were to hold the wheel and press on the pedals then you will apply a clockwise force to the sprocket relative to the wheel.  (Note it is possible, in theory, to unscrew the sprocket while freewheeling).  The reason that there might be confusion is that when you are removing a cluster from a derailer set up you need to loosen a lock ring to do this you apply  a clockwise pressure to the cluster (to stop the freewheel from rotating) and an anticlockwise pressure to the lock ring  (kind of the opposite of the Rohloff). 

Davidd55

Cost me $199 (80 QUID)

There is no easy way to say this David but you were ripped off.  There is a special tool for removing the sprocket but it isn't expensive - you also need a quality, workshop, chain whip (note I have now personally snapped two lesser chain whips!).  A good bike shop, that knows which way to remove a Rohloff sprocket, should get the job done easily in 5 minutes.  I would be expecting to pay £10 absolute max!

Stutho

 





 

[freddered]

Thanks Stutho

Durrr, I was a bit thick and now I have remembered which side my chainring is on it's obvious.

Re.  £80 for sprocket removal.  I think you bought the LBS a new chainwhip.
Unless he bought the tool himself I would expect my LBS to say "forget it, it only tool a minute" (as long as I looked like I was going to buy something from his shop).

It's like a Car Tyre garage removing a wheel to quickly check if your wheel is damaged isn't it?  I'd tell them to stick it up their ar*e if they charged me £80.

[freddered]

I bought the Sprocket removal tool and let  "Just Bikes" of Andover use it to remove sprocket.  I watched him do it, it took less than 30 seconds (after some grunting) and cost me £4 (their min labour charge) so I won't bother with a chain whip and vice because it's only likely to happen every couple of years.

Note.  I printed off Andy B's instructions for my LBS.  It's worth doing because LBS didn't really believe it should spin off anti-clockwise until I showed him instructions.

[freddered]

I just found loads of my Rohloff Oil was on the Garage floor this morning.

Does the Sprocket form an oil-seal?  The sprocket was loose, waiting to be flipped today.  I have an oil-change kit ready and waiting but I'm reluctant to put new Oil in if it's going to leak out again.

Can removing the sprocket break an important seal?

[Cake]

Did you leave the wheel upright overnight Freddered?  I know you're not meant to lie the bike on its side for any great period of time for that reason....  I'm sure you know that anyway!

[stutho]

Hi freddered,

Does the Sprocket form an oil-seal?

YES!  Once the sprocket is off you need to keep the wheel on the LHS.
 If you have lost significant oil then I think an oil change would be a good idea, as soon as you have the sprocket back on (don’t forget the copper grease).   Rohloff claim that you can't loose enough oil from the g'box to do any damage, but on the other hand why push the envelope  when you have an oil change kit sitting on the shelf.

All the best

stutho

[freddered]

Thanks Stutho, that's reassuring.

I'll go out for a few miles to tighten the sprocket up and then do an Oil-change.

[daviddd55]

Thanks Stutho

Durrr, I was a bit thick and now I have remembered which side my chainring is on it's obvious.

Re.  £80 for sprocket removal.  I think you bought the LBS a new chainwhip.
Unless he bought the tool himself I would expect my LBS to say "forget it, it only tool a minute" (as long as I looked like I was going to buy something from his shop).

It's like a Car Tyre garage removing a wheel to quickly check if your wheel is damaged isn't it?  I'd tell them to stick it up their ar*e if they charged me £80.

No, no, no - 80 quid was for the whole setup - chainring, sprocket and chain!! And fitting!!

[stutho]

That not too bad... but I would still recommend doing it all at home and saving a few £££.

[ALMEIDA]

Hi,

please have a look on the following link. Believe me, it's a pretty good instruction.

http://forums.mtbr.com/showthread.php?t=250041

ALMEIDA

[jawj]

Phew, just got my sprocket off! Blimey that required some heaving and hoing.

...you will require access to a large vice, which is mounted securely to a workbench.

Yup, Andy might be right there. I had to zip tie a pole to my chain whip and then use this hybrid tool along with a massive adjustable spanner in the manner of a rowing machine whilst sitting on the floor to free the sprocket. Good times!

(Crawls away with spinal injuries to fetch the GT85 to mop up more spilled Rohloff oil on carpet...)

[redcogs]

Hi. A recent issue arose on replacing my socket with a new one, and i thought that people ought to be aware.

i had reversed my socket quite some time ago because the teeth had become quite worn on one side.  Reversing it corrected the problem, and obviously extended the life of the item significantly.

However, be warned..  If you allow too much time to elapse prior to replacing the socket with a totally new one, you could well face the same problem as me - ie, the cog teeth had become so worn that they were very weakened, and the chainwhip, when applied with the necessary force to remove the cog, began to snap off the teeth of the cog one at a time. 

What was almost a disaster was rescued when the cog did finally loosen before the cog was irretrievably weakened by tooth loss thus preventing the use of a chain whip.

i would add that this near catastrophe was entirely my own doing - i had definitely waited for far too long before fitting a new cog, but its the sort of job that is easy to overlook, especially because we are so unused to having to perform any maintenance thanks to Rohloff and Thorn!

So, i would recommend keeping a pretty close eye on the state of your rear cog once you have reversed it.  Better safe than sorry.

[jawj]

That's a good bit of advice, Redcogs, glad you managed to remove it before all the teeth gave up - that would have been a nightmare!

It leads me on to an almost related subject...

The following may cause a little controversy as I've read previous threads on here about people comparing how many tens of thousands of miles they can squeeze out of their chain.

To those people I say: ditch your chain before it wears out!

I'm pretty certain if I'd followed that advice and do what I normally do and replace my chain very regularly (4-5 months, though this does of course depend on your mileage and the conditions) then I wouldn't have had to reverse my sprocket for a jolly long time yet. I'm aware too of the threads in this forum about how a Rohloff hub can actually save you money in its lifetime (tenuous...) but I use a Speedhub cos it's bombproof and there's a lot less cleaning of solid black crud off jockey wheels to do (you all know what I'm talking about!) I service and clean enough peoples' cacky bikes every day that I'm very put off doing any maintenance to my own bikes. The most shameful example of this is a chain of mine that was only several months old that I just didn't fancy cleaning: it got replaced...

Terrible! I know! But it stops sprockets wearing out...!

[stutho]

Redcogs,

How much mileage did you get out of the sprocket, before you tried to remove it.  This is not a criticism - I am just mealy curious.  I recently reversed my sprocket after 12000 (mainly road) miles on one chain.  There seamed to be very little wear  on the sprocket, the chain ring  however was badly worn (I doubt that I will get another 12000 miles out of the other side)

jawj,

I have to say I disagree with you, you can run much higher mileage per a chain with a Rohloff. A chain on a good single sprocket chain  run experiences FAR less loading than a derailer set up - no lateral or twisting loads.  With a derailer everything has to be keep  in a tight tolerance else you wear out an expensive cluster - again not a problem with  the Rohloff so you can run a chain far beyond the normal 1/16" in 12 rule.  If I had changed the chain as often as on my derailer set up then I would be looking at having bought at least another 3  chains at £15  = £45 that I haven't spent.  By the time I  do need to change my chain ring and my sprocket I should of save ~£90 in new chains alone which more than covers a new sprocket and chain ring