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It is a decade since Rohloff first introduced their revolutionary 14 speed geared hub.I was interested in the hub at the time, but I didn’t want to buy something which I felt may not work properly and which I knew I would never be able to mend.
We were persuaded by some strong willed customers into building a few custom bikes equipped with Speedhubs and hearing some positive feedback from the happy owners, I decided to contact Rohloff myself (I reasoned that, with the passing of the years, Rohloff would have identified and cured any problems during this time.)
“What problems have you had and what is the service life?” I asked, getting straight to the point, after introducing myself.
“ No joke, Andy, but we have never had a hub fail, so we can’t tell you the service life, but some of our customers have covered 70,000km of world travel” was the reply from the product manager, Carsten Geck.
There followed more emails, my design for a frame was approved. This is equipped with an eccentric BB to adjust chain tension, whilst using socketed vertical drop outs, (which we know produce the most reliable rear ends for touring bikes.)
We had more conversations about how low you could gear the hub, Rohloff have calculated that the maximum torque, that the hub will reliably withstand, is slightly more than could be produced by two world class athletes on a tandem using a 38 tooth chainring and a 16 tooth sprocket. This is the lowest gearing that they will sanction (which is equivalent to a 22 tooth chainring and a 32 tooth sprocket in a derailleur system.) I use very low gears and I wanted even lower ones! Whenever I get the opportunity, I like to travel on dirt roads, over high mountains, with medium-weight camping and cooking kit and up to 1 week’s supply of food... I reasoned that, as I was certainly not a world class athlete, not particularly strong or heavy and there is only 1 of me (!) that I should be able to use a lower gear than would be safe for the two world class athletes on their tandem! Carsten agreed with me, but maintained that if I chose this route, it would be at my own risk…no exceptions!
I decided that I would use 36 x 17 (11.67% lower than the lowest Rohloff would give warranty for) I felt confident that I would never produce the level of pedal force of 1 elite athlete, even with an 11.67% mechanical advantage!
I built 2 long-wheelbase eXXp ( e double ex pee) Adventure touring bikes with Speedhubs and Fiona and I set out in Feb 03 to ride as many mountain gravel roads as we could find in Tasmania…there were plenty!
The bikes were better than good…they were sublime. I liked the Rohloff hub so much that my eXXp has been joined by a lightweight, sporty bike with a Speedhub; this is geared 39 x 16!
like the solid build of the Speedhub, it was originally built as an all-season MTB hub, for use in Northern Europe’s extreme conditions…it is well sealed, all the internals run in an oil bathI like the fact that the “indexing of the gears” takes place inside the hub, this means that the twist grip, although beautifully made to enable easy replacement of the cables, is a low tech item…there is little to go wrong with it (unlike current derailleur shifters)
The twin-cable system means that there are no return springs to fail, either in the shifter or the hub.
I like the way that the next gear (up or down) is only a simple twist of the shifter away… none of that “changing up a chainring and down two sprockets.”
I love being able to change gear without pedalling, it is difficult to express how really useful this is.
It is great not to have a derailleur hanging low down waiting to be knocked.
The smaller chainring and sprocket (and lack of rear derailleur) means that the chain is less likely to cover your leg in black muck.
I like the way Rohloff have engineered the sprocket to be double sided…wear it out and then turn it round and wear it out again, only the British, Scandinavians or the Germans would think to do this.
I like the way the gears never “jump” or slip…you feel really confident pedalling, or changing gear, when out of the saddle!
I like the absolute silence of pedalling it, in gears 8 to 14, once it is run in.
It would be too much to hope that there would be no dislikes, but they are few.It is a shame that the hub is only available in 32 holes, but I have been persuaded that 32 spokes, bedded in widely spaced flanges with no wheel dish, are stronger than 48 spokes on a dished wheel with the narrow flanges necessitated by 9 speed cassettes.
It is a pity that fitting the (22.2mm dia.) shifter to standard diameter (23.4 mm) drop bars is impossible…there are solutions but they are all inelegant. I personally prefer swept-back riser bars, with inboard mounted bar ends for touring and general cycling, but there are those who don’t.
I don’t enjoy the noise in gears 7 to 1, especially the noise in gear 7…but I can easily live with it, because it is the noise of precision parts rotating and meshing at speed, the hub does get quieter with the miles and I am in gears 8 to 14 most of the time!
I don’t like the fact that you have to back off when changing between 7 and 8 and 8 and 7. If you don’t back off, you will stay in the highest gear (14th) until you do!
I quizzed Rohloff about this and they said that it was because of a safety feature that they had engineered into the hub! The Rohloff 14 speed hub is a seven speed hub with a set of (internal) reduction gears, giving a second set of 7 speeds.
Gear 7 is the top gear in the low ratio.
Gear 8 is the bottom gear in the high ratio.
To shift between them requires two separate things to happen, from 7 to 8 the hub needs to change from low ratio into high ratio and from top gear into bottom gear, if Rohloff had attempted to make both things happen simultaneously, wear would have tended to make one shift happen before the other…if it changed to bottom gear first, then you would momentarily be in 1st gear (bottom gear/ low ratio) the pedals would “fall away from you” and you may have had an accident.
So Rohloff engineered the shift to occur in two phases;
On the way up the gears, it first changes into high ratio, then into bottom gear.
And on the way down the gears, it first changes into top gear, then into low ratio. The fail-safe way it has been engineered, does mean you need to back off, which is a nuisance, but it is only a nuisance and not a danger, and much easier than changing chain rings with a derailleur! It is easy to know when you are in 7th gear because of the noise, so the 7th to 8th change is easy to make allowances for.
I dislike the weight! It does weigh a little more than the items it replaces, but the frame also needs some extra provision for the hub, the fact that all the weight is at the rear of the bike makes it feel heavier than it actually is. But to be fair to Rohloff, when you see a cut-away drawing and you see all those ball races, labyrinth seals, and needle bearings…when you see the quality of the machining you realise they have done remarkably well to make it as light as it is! This is German engineering at its finest…it gets better as it gets older…I am not going to cite the high cost as a negative feature because, looking at the quality of this product it is actually an engineering bargain, beyond belief! Goodness only knows how many £££’s worth of shifters, cassettes, derailleur, chains, chain rings and rear hubs you would need to buy during the service life of the Rohloff Speedhub! Or how many jammed chains, slipped gears and messy hands you would avoid.
Rohloff gear ratios (in inches) 26” wheels 526%
Average 13.6% difference between gear ratios. (This varies between 13.26% and 13.92%)
(See also my Online Gear Calculator -- Sheldon Brown)
sprocket
Three typical, modern derailleur set ups, (gears shown in gear inches) (X = bad chain line avoid using)
The 3 red highlighted possibilities are to be used at the owner’s own risk.Rohloff will not give a warranty on the hubs when a gear with an input ratio smaller than 38 x 16 (2.375:1) is used. This (38 x 16) ratio is permissible for use by world class athletes (permissible even for 2 athletes, on tandem)
The diameter the wheel and the gear ratio produced are not relevant…it is the input ratio which is critical…Rohloff state 150 kg pedal force (!!!) with 170 mm cranks as max. input, if exceeded, this could damage the hub as easily in 14th as it could in 1st
In our opinion 38 x 16 is an ideal general touring gear, some may say it is too low, but if you are fit enough, or can get fit enough to spin 14th gear at a knee-saving 100rpm for 1 hour you would travel 43.377 km (27.11 miles) on 26” wheels!
You may feel, especially if you are older and/or used to spinning low gears, that you are unlikely to develop the pedal force of a world-class athlete, so you may wish to take personal responsibility for the hub and use these “forbidden” ratios…it is your choice!
There are no limits imposed by Rohloff, on how high a gear you can use, there is a double-sided 15 tooth sprocket available. Rohloff also make a 13 tooth sprocket, but this is only single sided, and is positioned slightly further outboard of the hub.
11th gear is direct drive and should be the most efficient; consider this ratio carefully, because ideally, this would be your most used gear.7th gear is always the noisiest and the 7th to 8th and 8th to 7th gear change needs to be made without too much transmission load on the hub (see “living with a Rohloff Speedhub”), so ideally, gears 8 to 14 (which are also the most efficient) should be carefully chosen to allow them to be used most of the time. Gears 7 to 1 can be saved for fairly steep hills, steep hills and really steep hills, when you are tired and heavily laden.
A comparison between 3 modern derailleur set ups and similar gear ratios obtainable with Rohloff.
a = typical modern MTB set up, 22/32/44 chain rings and 11-34 cassette frequently recommended for use on expedition bikes (and many fast touring 26” wheel bikes)… excellent 618% range, 15 “different” gears although 64 and 67.3 are almost too close (5.16%) to qualify as different …notice how the % gaps in the gears becomes large with the derailleur set up in the higher gears…do you really need a 104” gear on an expedition bike? Wouldn’t the closer ratios of the Rohloff, beyond 55” be much more useful?
11th gear will enable you to travel at 22.19 kph (13.87mph) at a modest 75rpm!
The 17.2” bottom gear may seem very low, but it will enable you to spin at “an easy to keep your balance” 48.5 rpm when climbing very steep hills at 4kph (2.5mph)
Rohloff
67.3
b= fairly common (if rather too high in our opinion) fast-touring bike ratios, the 537% range is slightly up on the Rohloff.
There are 14 “different” gears but 85 and 89.1 are very close (4.8%)…the gap between 89.1 and 104 is also quite large at 16.7% (22.8% greater than the average 13.6% between gears with Rohloff.
Rohloff
c= All too frequently used combination, when it is realised that a “sexy” 30/42/52 chainset with a tight 12-25 cassette does not produce a low enough gear for the owner’s athletic ability! Without supreme fitness and condition, it is interesting to speculate on the service life of the owner’s knees in the122.9” gear! The percentage range is very good at 504% and there are 14 “different” gears, although 48.8 and 52 and 91 and 96.6 are too close (6.6% and6.2%) The gap between 96.6 and 112.7 is quite large (16.7%) However, some tandem crews may feel that these would be an ideal set of ratios for their use…they would need to be a strong team, or keep away from very steep hills!
Rohloff
* = change up 1 chainring and down 1 cassette sprocket to select this (higher) ratio.
** = change up 1 chainring and down 2 cassette sprockets to select this (higher) ratio.
Thanks to St. John Street Cycles for permission to reproduce this article. © Rohloff GmbH 99-- Technical Specications subject to changes
Rohloff Hubs from Harris Cyclery
Rohloff English-language Home Page
Rohloff documentation in PDF format
Custom Wheelbuilding
Wheels hand-built by Harris Cyclery
We build custom wheels, with care and attention to detail. Standard charges:
We will re-use your old hubs if you wish, but will not use used spokes nor rims.
- $40 each for wheels with 36 or fewer spokes.
- $45 for 40 spoke wheels.
- $50 for 48 spoke wheels.
- $10 for cutting out and prepping a used hub.
- Butted spokes (DT or Wheelsmith) $1.00 each.
If you bring in existing wheels to be rebuilt, add $10 per wheel for cutting the old spokes, cleaning and prepping your hub.
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