Thorn Cycles Forum
Community => Rohloff Internal Hub Gears => Topic started by: AndrewC on September 02, 2010, 05:22:20 PM
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Going to be doing this shortly, all hints & tips welcome.
The Rohloff manual doesn't seem to cover the process, concentrating on the internal variant ?
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Rohloff Manual Section 7.3 pages 80-82 seems to cover it...
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Ah Thanks.
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Reprinted from RBT. The respondent, Chalo Colina, is a machinist, bicycle mechanic and builder of circus bikes; he owns several Rohloff gearboxes.
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Andre Jute wrote:
>
> While I'm ordering service/spare parts and tools for the first annual
> service of my Utopia Kranich and its Rohloff gearbox at about 2000km,
> do I need to order spare gear cables for my EXT klickbox, either for a
> routine swap-out or to keep on standby for a likely breakage. I note
> that Andy Blance of Thorn reckons that even the dicier internal cable
> setup is very unlikely to break before 10K.
>
> Blance also says the EXT gearbox cable on the Rohloff is standard
> dimension normal brake cable. (The internal cable is apparently
> thinner.) Has anyone used standard brake cable, outer and lining
> instead of the Rohloff's own supply? With what result?
Rohloff's external clickbox and shifter are wired with two totally
normal 1.2mm shift cables. You don't have to stock special spares for
that job. Depending on your setup, you might need tandem-length
cables. A quick survey with a tailor's tape measure will tell you if
you need to keep some extra-long cables handy; normal shift cables are
2.0m long.
Rewiring a Rohloff shifter is an _odious_ job, though. You have to
get a whole series of operations exactly right, in the right order,
before you fasten the cables down. The cables are fastened with grub
screws, and once tightened even lightly, they can't be reinserted into
the clickbox drum again. So if you forget any detail in the cable
component stack or in the routing of the cable, you have to begin
again with new cables, starting at the shifter spool. I think the
most times I have had to do this at one sitting is four times in a
row. (It's not just outright mistakes that can stop the show. If it
doesn't feel quite right and you want to try changing something, you
have to start over from step one.)
When the time comes to replace Rohloff shift cables, have every single
bit ready in advance. Have every tool available that you might want--
bench grinder, fourth hand, precision ruler, whatever. Have the
printed instruction sheet in hand and refer to it at every step. Do
not reuse a single piece of housing or ferrule, lest this seemingly
sensible and economical measure require you to repeat the job.
But hey-- at least it uses standard cables.
Chalo
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And here's another owner of multiple Rohloffs, Pete Creswell, in the same RBT thread with more good advice about measuring the cable:
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Per Andre Jute:
>Thanks, Chalo. I've saved this post. From the video on the Rohloff
>site I thought it looked like a tricky job -- and remembered that
>before this you described it as "odious"
I'll concur with "odious".
For me the recurring problem was getting the length of cable that
protrudes past the housing exactly right.
To that end, I cut a piece of housing to exactly the right
length.
I've done several replacements with the housing piece as my
length guide and haven't had any problems.
But I still have a half-dozen shift cables ready just in case
when I start the job.
Pete Cresswell
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I assume you already have:
Rohloff cables explained -- Andy Blance Nov 2005, PDF from Thorn site
Cable changing video -- movie from Rohloff site
HTH. Good luck.
Hobbes
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Well that was easier than I was expecting.
The cable outer suggested & supplied by SJS didn't have a separate inner, so I just carefully cut it to match the original ones and put caps on.
I used a 200mm piece of the outer as a guide when cuttting the cable. I'm not sure how tight the pulley grub screws need to be. Might give them some extra welly to be safe, but it's all together & shifting seems nice & smooth.
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I'm resurrecting this old thread because I don't understand why you can't reuse the old housing. I'm thinking of pulling the existing cables and replacing, just to get some practice with this procedure. But the bike only has 6000km on it, so I don't see why I would need to replace the housing.
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There's a handy video of this procedure on the Rohloff site:http://www.rohloff.de/en/technology/workshop/videos/external_cable_routing/index.html (http://www.rohloff.de/en/technology/workshop/videos/external_cable_routing/index.html)
As to why replace the outers... no idea, but if you're doing the inners, why wouldn't you? It's not expensive, and not particularly difficult. Also, I think the liner can get chewed up if you leave it too long.
I'm about to do my external box cables, as the outer has been torn. Handy time to be bringing up the subject.
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As to why replace the outers... no idea, but if you're doing the inners, why wouldn't you? It's not expensive, and not particularly difficult. Also, I think the liner can get chewed up if you leave it too long.
I'm about to do my external box cables, as the outer has been torn. Handy time to be bringing up the subject.
If the bike were more used and I was doing this as standard maintenance, I would replace the liners. But this is more for practice for field repairs, in case I ever need to do that.
I've read some of the old threads here plus the comments in Living with Rohloff. The official Thorn view, if I'm not mistaken, is to use standard brake housing (which is more durable than shifter housing) and standard 1.2mm shifter cable. To accurately measure the 200mm of shifter cable that protrudes beyond the housing, cut a 200mm piece of brake housing and bring that along in the field repair kit, along with spare cables.
I sewed up a cordura sack, about 13cm square with hook-and-loop closure weighing about 15g, to hold the spare cables, since otherwise the cables unfold and make a mess in the repair kit:(http://frankrevelo.com/hiking/sewing_bikemisc_cableholder.jpg)
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Very good. If you have everything prepared that way, you'll never need it!
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Rohloff cables are 1.1mm, its important especially with the Light shifter to use either Rohloff or Fibrax for Rohloff cables as the heads on Shimano cables are too big and deform the plastic cable drum.
Hope this helps.
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Rohloff cables are 1.1mm, its important especially with the Light shifter to use either Rohloff or Fibrax for Rohloff cables as the heads on Shimano cables are too big and deform the plastic cable drum.
Hope this helps.
Yes, it helps a lot. The 1.2mm was a typo, I knew 1.1mm was correct. But the need to use Rohloff or Fibrax cables is news to me. I have a Nomad MKII purchased in Jan 2012, with this type of shifter (http://www.sjscycles.co.uk/rohloff-14-speed-handlebar-twistshifter-light-for-speedhub-500-14-8206-prod25413/) which the Rohloff guide calls simple "Twist Shifter NEW". Is this the right cable:
http://www.sjscycles.co.uk/fibrax-thorn-teflon-coated-11-mm-gear-inner-cable-wire-2200-mm-long-prod19903/
If so, I'll want to buy in bulk, since shipping to the US is so expensive.
Another question: can I use standard brake cable housing for the Rohloff shifter ex box? I'm hoping yes, since I don't want to have to order cable housing from the UK as well.
Finally (and this question is for either Dave Whittle or anyone else who wants to chime in): what parts of the Rohloff shifter and ex gearbox are likely to break during use, or break or get dropped on the floor and disappear somewhere during the cable replacement process (remember, this is a beginner doing the job). I ask because I'll want to order spares as part of my order, again since shipping is so expensive.
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The following is Dave Whittle's reply to an email I sent:
In production we use these http://www.sjscycles.co.uk/fibrax-fibrax-11mm-tandem-inner-gear-cables-rohloff-compatible-3500-mm-prod28660/ they work really well and we spent a considerable amount of time with Fibrax and Rohloff getting the specs right.
You can use any 5mm brake outer casing you like. The important bit is not to lubricate the cables and to fit sealed ferrules http://www.sjscycles.co.uk/rohloff-shifter-cable-housing-cap-set-8703-prod16491.
You could drop the grubs screws I suppose http://www.sjscycles.co.uk/rohloff-grub-screw-bayonet-connectors-8570-prod16459/ they live in the alloy cable drum.
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Just built my first Rohloff equipped bike (Surly Disk Trucker)
I looked at the Rohloff video for installing cables to EX box.
I followed the instructions but the inner cables were too short to wrap around the pulley and install in the EX box.
In the video it looks like the 200mm measurement is from the end of the outer cable housing, ie without the ferrule, is this correct?
I tried again this time measuring the 200mm with the ferrule on. Now it fits ok.
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Yeah, I measured from the fitted ferrule. It's hard to see in the video, I think.
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ferrule ??
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ferrule ??
The little metal caps that go over the ends of the cable housing.
Best,
Dan.
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Yeah I thought that but couldn't figure how it would make much difference tbh , worth remembering tho ;)
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I'm resurrecting this thread because I finally got around to doing this.
This was for practice only, so I didn't replace the housing, just the shifter cables. Lots of dust inside cable box, so I cleaned that out. As Andre noted, tightening headless screws on cable pulley mangles cable ends, after which they won't fit into tiny holes on cable pulley, so make sure everything is setup correctly before tightening. It would also be wise to superglue ends of cables immediately after cutting, to prevent fraying. I managed to bungle things the first time, by forgetting to install the cable adjusters before tightening the headless screws. Since I had extra cables on hand, I simply cut replacements.
I also pre-cut spare cables for my repair kit, in the obvious way: install cables in shifter, measure, cut, superglue frayed ends, remove from shifter, place in repair kit. Spare cables weigh about 25g. Cable housings are slightly different lengths, so pre-cut cables are not interchangeable. To know which pre-cut cable is which, I painted head of gear 1 cable black. I also cut 200mm of cable for repair kit, to allow field measurements, in case I forget about black colored head or black coloring wears off somehow. I regret not cutting two sets of pre-cut cables, just in case I bungle the field replacement procedure.
Dave Whittle is a more experienced bicycle mechanic than me. Here's an idiot's guide to what can be lost while replacing the cables: cable stoppers, ferrules, cable box torx screws, headless screws for cable pulley. I did drop the cable stoppers, but there were easy enough to find. Thankfully, I was smart enough not to unscrew the headless screws all the way, because these tiny screws could be very difficult to find if they rolled far, especially during field replacement. I was also careful when cleaning and regreasing the cable box torx screws. The ferrules didn't come undone during the replacement procedure, but this is another thing to watch out for.
I wouldn't go so far as to call this an odious job. It's simpler than an oil change. And I strongly recommend you practice this procedure at home rather than trying to do it for the first time in the field on a long tour. Practicing at home is also the only way to get pre-cut cables for your repair kit.
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It would also be wise to superglue ends of cables immediately after cutting, to prevent fraying. I managed to bungle things the first time, by forgetting to install the cable adjusters before tightening the headless screws.
Oh yes, I've done two Rohloff EX box set-ups and managed to do this each time :-X
BTW if you're lucky (and I was each time) you can re-insert the cable ends....... just.
Oh yes I also managed to complete my wife's Rohloff conversion, everything cabled-up, all gears working correct, BUT cables were swapped. She now has gear 1 as top gear and gear 14 as bottom :D :-X Too much faffing about to be bothered changing it (plus the need for two new cables) so she has just got used to a reverse action.
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Good day to everyone.
Although I've had my hub for about three years its never had any maintenance other then oil changes, but now the outer plastic coating has come off my gear cables and I think the amount of force required to shift gear is increasing. More friction is my guess, so with this in mind can I ask a stupid question?
Why would you not lubricate the inner cables when inserting into outers?
I've always lubricated my cables when inserting them, it just seems to make sense.
What am I missing?
Thanks in advance for the replies
Jim
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Why would you not lubricate the inner cables when inserting into outers? I've always lubricated my cables when inserting them, it just seems to make sense.
Hi Jim!
I asked this same question of a cable/casing manufacturer once, and this is what they told me:
With modern delrin or delrin-like linings and die-drawn cables (very smooth and with little stretch), the liners are self-lubricating. The lining turns to a fine powder under the action of abrasion. If one introduces lube into the system, it can turn gummy over time and actually increase friction. Additionally, it was his opinion that lube running down the cable past the stops could actually draw grit and dust into the housings, also increasing friction and accelerating wear. Therefore, his firm did not recommend lubricating cables.
This does indeed seem counterintuitive and for many years, I did use Tri-Flow to lube my lined cables. I stopped after getting this explanation, and I have to admit...my cables and housings have remained smoother longer, especially since switching to die-drawn cables when they were introduced to market.I think the amount of force required to shift gear is increasing. More friction is my guess...
Mine, too. I suspect the cables may have worn through the linings. The most likely points are at entry, exit, and on the inside arc of a curve....so with this in mind can I ask a stupid question?
Jim, the only stupid question is the one left unasked!
Hope this helps.
Best,
Dan.