Any reason why I shouldn't use exposed cables ?

[MilitantGraham]

It's common practice with derailleurs to only use outer cables for the bends and have the inners exposed between the cable stops on the straight frame tubes, so why do Rohloff recommend full outers ?

Has anyone done it ?
Any reason why I shouldn't ?
It's for a tandem, if that makes a difference.

[il padrone]

Exposed  cables are used on racing bikes to minimise the effects of cable compression and facilitate prompt shifting. It's a bit less of an issue with modern SIS compressionless cable-housing, but old habits die hard in racing. With the Rohloff the cable housing is the old-style spiral wound housing that will compress somewhat, but as the indexing is all internal for the hub it is really not an issue. Having covered cables is more valuable especially if you tour, ride dirt roads, or ride in wet conditions as they keep your cables free of grit and junk. I prefer this.

Having said all that it is a choice up to you. My son recently set up a Rohloff on his bike and went with open cable along the top tube as the end-stops were there. I have suggested that closed cables have maintenance advantages but he does it his way, and it will probably be quite OK for a long time.

[phopwood]

The cables on a Rolhoff run a little loose, but as long as you have enough tension to hold the cable in the correct places you should be fine with exposed cables.  On my bike the cables are housed as far as the rear brake pivot and then exposed for a few inches to the Rolhoff cables joints.  I clipped them to the top tube using Rolhoff cables clamps.

But now you have said this I may try exposed cables when I have a bit of spare time one afternoon.

Peter

[David Simpson]

I have found that exposed cables are not good for rainy-weather riding.  The grit and dirt from the road gets onto the exposed cable, and near the cable enclosures the back-and-forth movement of the cable brings the grit into the enclosed section.  If you never ride in the rain, then exposed cables may be fine, but for me (year-round commuter in a rainy climate) I much prefer fully-enclosed cables.

- Dave

[geocycle]

In general I agree with Dave, it is better to cover if possible.  That said, I have an internal rolhoff with 6" of exposed cable and have never had a problem with the exposed section. I'd prefer to have it fully enclosed.

[Danneaux]

If one is running exposed mech cables in foul conditions, fitting a v-brake bellows cover and a small cable tie to keep it in place go far toward avoiding problems and keeps the housing runs both cleaner and drier. I did this for friends with MTB seatstay-mounted cable stops and this greatly reduced problems of dirt/mud/water ingress along the cable.

Should work as well with Rohloff cables, though I too much prefer closed runs if possible.

Best,

Dan.

[MilitantGraham]

I was thinking of a mountain bike when I asked the question, forgetting that there are more touring cyclists than mountain bikers here, which is why I thought exposed cables would be better.
With 2.5m of inner wire and only 1m of outer cable, it's easy to unclip the outer ends from the frame and slide them back and forth along the inner wire to clean everything and distribute the oil.
With full length outers, you are limited to trying to get the oil in from either end, although Middleburn cable oilers help.
I'll give it a go then, with some Shimano seals on all the exposed ends.

[jags]

don't suppose you have a photo of those shimano seals on your bike.

[il padrone]

With 2.5m of inner wire and only 1m of outer cable, it's easy to unclip the outer ends from the frame and slide them back and forth along the inner wire to clean everything and distribute the oil.

Not so easy with the Rohloff. With a MTB running derailleurs you do this by setting the gear in largest sprocket, then releasing the shifter to top gear. This gives you a good measure of slack to slip the outers out of the stops. With the Rohloff there is no such release possible (full length or exposed sections). You might be able to get some extra slack by setting the cables a bit slack on the EX box and using the barrel-adjusters to take up the slack, but I don't know whether this would be enough to get the housings out of the stops on the frame.

With full length outers, you are limited to trying to get the oil in from either end, although Middleburn cable oilers help.

With my full length outers, in 3 years of riding on all sorts of roads and bush tracks, I have never lubed the cables. They run just fine.

[MilitantGraham]

Not my bike, but here's how they are assembled on to the frame.



And here's what it looks like with the two parts plugged together.

...in 3 years of riding on all sorts of roads and bush tracks, I have never lubed the cables

You're not trying hard enough. 



I could always cut the inners 5mm too long, that would then definitely give me enough slack if I wind the adjusters all the way in on the external box, if there wasn't enough already.
Worst case scenario, take the cover off the external box and drop the little pulley out. It's worth taking it off every now and then anyway to clear the mud out.

[il padrone]

You get mud in your EX box ??

You need more grease then. Despite all sorts of bush riding I have still plenty of good grease in there..... and I've only replaced it twice I think, despite the alleged service interval of every 500kms 

[peter jenkins]

Hi Dave,

for me (year-round commuter in a rainy climate)

Where is this terrible place you live in?

Regards,

pj

[David Simpson]

Where is this terrible place you live in?

Sorry for being ambiguous.  I'm a year-round commuter, but it isn't rainy all year around (thankfully!).  I'm in Vancouver.  It's rainy most of the winter, although we normally have a couple of weeks of where there is some snow.  The summer are really nice, with only a few rainy days.

- Dave

[jags]

Dave thanks for posting the photos,as the man said you learn something new every day.

be sure to wash that bike.

[John Saxby]

Hey guys, go easy -- Dave lives in a temperate rain forest, 'cept most of it's been cut down in the Lower Mainland...But the winter rain continues even if there are now many fewer trees.  Brazilian friends make a neat jeu de mot about "Van-chuver", "chuver" being the Portuguese verb "to rain".  Then again, as friends beyond the mountains regularly remind me, "At least we don't have to shovel our winter precip."  Some years back, a colleague phoned to say she was visiting Ottawa. This was in mid-Feb., so I said, "Better bundle up, Susie, it's -25 today."  She said, "John, I don't care, I haven't seen the sun for forty-two days!"  Let me go on record & say that in the many times I've visited Vancouver, I've never been caught in a prolonged grey-rainy spell -- never even been in Van when it's been raining, for that matter, weird as it seems.  When I was there last July, everyone was grumbling about how hot it was...