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Buying a new bicycle raises a few questions. Should your shiny, new two-wheeler be a sporting model or is ride comfort more important? Where will the bike be used, on mountain trails or paved asphalt?

There are also plenty of bicycles types from which to choose, from lightweight racers and trekking bikes to mountain and commuter models.

But one key question often goes unasked by people when purchasing a new bike — what is the best drivetrain option?

These days most bikes that customers buy are fitted with derailleur gears which have exposed multiple sprockets in both the front and rear.

What people might not realize is that internal hub gear systems are not only a viable option, but they also have a lot going for them — especially for cyclists not terribly keen on bike maintenance.

“The best derailleur system is no good if it is not looked after properly,” German cycling writer Sebastian Boehm said.

He is convinced that most owners do not maintain the gears of their bicycle properly and, therefore, would be better served by hub gears in which the mechanism is enclosed inside the hub of the rear wheel, protecting it from the elements.

It all comes down to mechanics, says Boehm, because hub gears are more resistant to the dirt and grime of everyday riding whereas derailleur systems are exposed to the elements. They need regular oiling and adjustment to perform at their best.

Despite the benefits, more bikes are sold with derailleur gears than with hub systems.

Germany’s industry body, the ZIV, estimates that derailleur gears cycles account for 65 percent of all bikes sold. Experts, however, agree that internal seven- or eight-speed hubs are far more robust.

Hubs are sealed against water and dust with a lubricant inside that hardly ever needs attention throughout the life of the bike. The chain is also generally more heavy-duty and less prone to wear.

On the other hand, derailleurs are more mechanically efficient and offer a much wider range of gear ratios for hilly terrain and fast downhill work.

Both systems are operated by a cable, but derailleur systems require multiple cables which are also prone to wear and tear.

Hub gears, however, allow for a chain guard which can be critical when it comes to preventing dirty trousers or socks while commuting.

The only downside is that the guard and rear wheel must be removed in the event of a puncture.

“Many hub gear manufacturers guarantee up to 50,000 kilometers of maintenance-free use,” Boehm said.

This contrasts starkly with derailleur systems which begin to show signs of wear at around 500 kilometers if the owner does not oil and clean the chain regularly.

Bicycle dealers are well aware of the advantages of hub transmissions, “but they often neglect to pass this important information on to their customers as they are more interested in offering after-sales maintenance and repair,” Boehm said.

Most derailleur systems feature a total of between 21 and 27 gears although many combinations of front and rear sprockets overlap, reducing the overall number of useable combinations.

Modern hub systems generally offer eight separate ratios, but industry leader Shimano recognized the demand for more sophisticated hub systems and has announced an 11-gear package that will hit the streets in September.

Boehm recommends spending around 500 euros ($650) for a decent two-wheeler.

The price range includes a wide selection of usable city and trekking bikes (these have conventional 28-inch road wheels instead of the smaller 26-inch rims fitted to mountain bikes).

Such models usually come with an eight-speed hub as standard. For a derailleur model of the same quality, prices start at 900 euros.

When buying an internal hub bike, customers should be particularly aware of cheap package deals as they can be deceptive.

There is a tendency for makers to mix and match cheaper and high-end components from various available group sets in order to keep prices down.

“The components of the drivetrain should harmonize with each other since the weakest link will eventually cause the problems,” Boehm said. To ensure longevity the rear gear cogs, hubs and gear change levers should all be from the same group set and maker.

The ease of changing gears varies between hub and derailleur systems. “Older riders tend to have fewer difficulties with hub gears since they find using them to be more intuitive,” Boehm said.

Electrically assisted gear systems are still uncommon, but will probably become more widespread soon.

Shimano’s Dura-Ace Di2 road bike system features gear levers with an electronic shifter to move the chain between the sprockets and chain rings much quicker than a mechanical system.

There are no cables involves and the device even “trims” the gears to avoid chain rub which often occurs when ill-adjusted gears fail to mesh.

Average bike riders probably do not care how fast they change gears as long as everything remains reliable.

Boehm believes it will be some time before this technology trickles down to more affordable bicycles. 


DPA