Hub of the matter

Share

Internal hub gears have many advantages over the cumbersome derailleur system, finds Rowan Lamont.

Many riders have fond memories of the Sturmey Archer three-speed hub gear on one of their early bikes. Hub gears have been around for quite a while – Sturmey Archer patented its idea more than 100 years ago ­– and they are currently undergoing a renaissance of sorts, with some big companies investing a lot of money into the technology.

Let’s face it, shoving a chain off one sprocket and onto another is not very sophisticated – even with modern stepped clusters and integrated chains, the whole idea behind a derailleur is agricultural. When they work they are brilliant, but some of their shortcomings appear when regular tuning and maintenance becomes a chore.

They are sensitive pieces of machinery that are exposed to the elements and requiring regular maintenance to keep running smoothly. They’re also very vulnerable to being knocked, damaged and even torn off if a wayward stick gets tangled.

An internal hub gear system is a very different beast. There are no external gadgets – all the gears, mechanisms and moving widgets are sealed within the rear hub. Most work on a planetary gear basis, which to you and I mean that it is similar to a car gearbox. There are no parts to get bumped or tangled, they are incredibly reliable, and require very little up-keep or maintenance.

All the systems on test had a twist mechanism built into the handlebar grip, which is great on flat bars but requires an adaptor for drop bars. The Alfine uses Rapid Fire buttons.

Riding with a derailleur there are many gear ratios that overlap: the small front ring and small rear cog may be equivalent to a ratio in the middle ring and bigger cog on the rear. There might be 27 or more gears, but only a handful are ‘true’ gears.

With a hub-gear system, the gear ratios are like walking up a set of stairs – each step being harder than the last. The exception to this is the very novel Nu Vinci system, that has infinite variability; instead of ‘stepping’ up or down from one gear to the next, the Nu Vinci transitions smoothly from easy through to difficult. More like an escalator than a flight of steps, but you still have to pedal!

Riding with a hub system is very different to riding with a derailleur. It is easy! Because you can change gears while stationary, you don’t have to plan ahead. For instance, stopping at a red light in a high gear, you can shift to a low gear and ride smoothly away when the lights turn green.

There are some down sides. Firstly, the range of rotation in the wrist only allows the rider to jump three gears in one ‘twist’. When cresting a climb with a derailleur system it is nice to be able to push the gears from the middle ring into the big ring and enjoy a big jump in gear range as you smash down the other side. This isn’t the case with a hub system, where it takes a few twists to jump ahead in the gear range.

The shifting isn’t always as crisp as with a derailleur, and can occasionally hang up, momentarily causing a loss in momentum. Not a problem unless you are in a hurry, which is partly why we don’t see them on the race scene. They also weigh considerably more than a derailleur system, which makes the rear wheel feel sleepy, the extra rotational mass requiring more force for the wheel to accelerate.

It is also a little bit fiddly to repair a flat or replace a tube on the rear wheel, but with a little practice you can master two techniques you can choose between: patching a tube without removing the wheel or learning the steps of disengaging the hub gear to remove the wheel.

Some commitment is required to convert your derailleur bike to a hub gear system: they are expensive and require a new wheel to be built. To maintain chain tension a dedicated frame with horizontal drop outs or an eccentric bottom bracket can be used, or a chain tension device can be added to a standard frame. When the time comes for a service a trained mechanic is needed, but due to their reliability and being sealed against the weather, this is only required once in a blue moon.

The new systems probably don’t signal the end of the derailleur, but they are very good alternatives that may suit your type of riding. Hub systems lend themselves to commuter bikes, load-carrying bikes, and touring bikes, where an uninterrupted journey is key. If you plan to ride for long periods of time over great distances, don’t like to fiddle with your bike, and tend to give it a hard time, a hub system is just the ticket.

Rohloff Speedhub 500 / 14

$1621–$2050 depending on the set-up you choose

  • Widest range of gears as well as the most gears on test (14)
  • Incredible reliability, even with 125 moving parts
  • 3 colours available
  • Disk brakes can be fitted
  • Only system available with a quick-release option
  • Occasional hesitation between shifts
  • No gear indicator to tell you which gear you are in

92%

A very hardy, reliable and trouble-free system that is ideal for big distance touring and mountain biking

Shimano Nexus

$180 for the 3 speed hub and shifter

The 8 speed hub, shifter and roller brake kit was $365 when last available

  • Versions with 3 and 8 speeds available
  • Coaster brake option (back pedal to slow down)
  • Big indicator to tell you which gear you are in
  • Very quiet
  • Some hesitation felt between shifts

84%

Perfect for urban commuting and getting about town

Shimano Alfine

$449 for 8 speed hub and shifter

$926 for 11 speed shifter, adaptor kit and hub

  • Versions with 8 and 11 speeds available
  • Superior performance over the Nexus
  • Crisp and precise gear shifting with no play felt through the cable
  • Rapid-fire button shifters or twist shift options
  • Needle bearings used to reduce drag and noise

94%

A well-refined system for high-end commuting or touring

Nu Vinci CVP

$799 for hub and shifter

  • Clever worm indicator shows where you are in the range of difficulty
  • A smooth, continuous feel
  • Simple internals using rotating balls improves reliability.
  • No miss shifts or hesitations when changing gear
  • Disk-brake option
  • Capable of managing very high torque loads – ideal for carrying

90%

Always in the right gear – great for carrying loads, tandems or commuting bikes.

Many thanks to Epic Cycles in Brisbane for their help organising test rides for this article.

 

Ride On content is editorially independent, but is supported financially by members of Bicycle Network. If you enjoy our articles and want to support the future publication of high-quality content, please consider helping out by becoming a member.

One thought on “4”

  1. Emailed to [email protected]
    I have been riding with a Shimano Alfine 8 speed internal hub for 18 months (~16,000km) and loving it. The hub comes into its own through winter riding months where gear changing is as smooth and direct as the summer, even though my bike is caked in road-grit and mud from the Yarra, Gardiner’s and Scotchman’s bike paths. Oh, and the time taken on weekends to maintain only two cogs at a time seems to agree with my wife.
    However, the review missed one important point of comparison between the Shimano and Rohloff hubs: gear change ratios. The gear change ratio is the change in gearing from one gear to the next, and corresponds to the ‘feel’ of moving up or down a gear. The Rohloff 14 prides itself on a constant gear change ratio of 13.6% meaning that the feel in increased gearing from gear 1 to gear 2 is the same as 3-4 or 13-14. In the Alfine 8 sp, the gear change ratios are all over the place, with 3-4 being 14%, 4-5 being 18% and then 5-6 being an eye-watering 22% (6-7 and 7-8 settle back to 16% and 14% respectively). The impact on riding is not positive, but manageable. For me, most of my riding on the trails is done in gear 5, and so if I have a bit of a down-hill, or the wind at my back, I just have to be very sure that I want to go up the full 22% to the next gear (6).
    Shimano have obviously noticed this issue for riders of the 8sp, I just did the sums on the new 11sp Alfine and apart from the change from 1 to 2 (29%), all other changes are between (the magic?) 13 and 14%. On this basis, sounds like the Alfine 11sp is the value buy.
    Simon Angus

    1. Are you able to explain what you mean by gear change ratios? I use metres development to understand the difference between gears. What do the gear change ratios offer to this comparison?

  2. Emailed to [email protected]
    There is no precise term here — ‘gear change ratios’ is my phrase.
    Rohloff (English translated page) uses ‘Gear increases’ (see:http://www.rohloff.de/en/technology/speedhub/technical_data/index.html).
    Shimano don’t mention it.
    To work it out, you take their stated ‘gear ratios’, e.g. ‘inner gear ratios’ at the bottom of the Rohloff page above, and simply divide (say) gear 2 by gear 1: 0.316/0.279 – 1 = 13.3 % [1].
    So whereas metres of development and gear inches tell you about how ‘hard’ a gear is, they are a property of one gear, not the change between gears. ‘Gear change ratio’ / ‘gear incease’ is the term I / Rohloff use for the change between gears. You will get the same percentages from doing the ratio between gears using meters of development or gear inches.
    Simon Angus
    [1] Which is not *exactly* 13.6% as Rohloff say — perhaps they take the average going up and down? .. 2-3 = 13.9% .. so average for 1-2 and 2-3 is 13.6% .

Leave a Reply

Your email address will not be published. Required fields are marked *