Modern bicycles fall into two drivetrain camps. The derailleur system moves a chain across multiple sprockets, while an internal‑gear hub hides all the gears inside the rear wheel. Let's dig in.
How each system works
A derailleur drivetrain uses a steel chain that runs from the crankset to a cassette mounted on the rear hub. Front and rear derailleurs shift the chain laterally, landing it on different sized sprockets; all gear changes happen outside the bike and are exposed to the elements.
An internal‑gear hub, by contrast, connects the crankset to a single sprocket on the rear hub. Inside the hub, planetary gear sets alter the gear ratio while the chain (or belt) stays on the same tooth. The entire gear mechanism is sealed behind a protective shell, keeping dirt, water and impacts at bay.
Range
Derailleur systems offer exceptionally wide gear ranges—modern 12‑speed cassettes can span 500 % or more. Because the hub itself contains few moving parts, derailleur setups tend to be lighter.
Internal‑gear hubs typically provide a narrower gear range—most cover 300–400 % - extreme climbs may feel cramped compared with a 12‑speed cassette.
Weight
Internal hub systems add a fair bit of weight onto bikes - you would barely notice it on an electric cargo bikes though.
Maintenance
Derailleur drivetrains demand regular upkeep. Chains, cassettes and chainrings wear and must be cleaned and lubricated frequently. Their exposure to dirt, water and debris can cause missed shifts or premature wear, and precise front‑rear coordination is required for smooth gear changes, particularly on steep terrain.
Internal‑gear hubs shine for low‑maintenance. Their sealed internals stay clean, eliminating the need to clean or lubricate multiple sprockets. Gears can be shifted while stationary or pedalling slowly, which is great for stop and go city cycling. Weather‑related durability is another plus: rain, snow, sand and mud have little impact on shifting performance.
Cost
The upfront cost of quality hubs, especially Rohloff, can be substantially higher than comparable derailleur groups.
What is best for cargo bikes?
Urban commuters who face mixed weather and frequent stops often favour internal‑gear hubs for their quiet operation, low maintenance, and ability to shift while stopped internal ‑gear hubs also reduce drivetrain wear and keeps the bike tidy.
Bottom Line
Derailleur systems excel where maximum gear range (like on very steep hills) and component flexibility matter most. Internal‑gear hubs shine for riders who prize low maintenance, weather resilience and the ability to shift at a standstill. Your decision should reflect the type of riding you do, the conditions you encounter, and how much maintenance you’re willing to perform. Whichever path you choose, proper installation and periodic checks will keep your bike running smoothly for years to come.
