Road, mountain and city bike hubs

Nexus and Sturmey-Archer: hub gears

A hub with internal gears contains a planetary gearset within its shell: the crown, satellites, and planet gear combine to gear up or gear down pedalling. The process was popularised by Sturmey-Archer, a Nottingham company founded in 1902 around a three-speed hub. Shimano offers it in their Nexus line, with three, seven, and eight speeds, featuring a roller brake or disc mount depending on the version. Protected from water and mud, the mechanism requires very little maintenance and allows for gear changes while stationary, at a red light.

Other wheel parts

Wheels also come in:

• Rims.
• Freewheel body.
• Bearings.
• Through axles.
• Wheel locks.
• City wheels.
• MTB wheels.

All wheels are gathered on the wheels page.

HG, XD, or Microspline bodies and Boost standard

On a rear hub with cassette, the freewheel body determines compatibility. Shimano's HG body accepts cassettes with a smallest sprocket of eleven teeth; Sram introduced the XD body to go down to ten teeth, and Shimano responded with the Microspline, reserved for its twelve-speed MTB cassettes. Spank Hex J-Type hubs come in several versions with the Boost standard: one hundred forty-eight millimetres spacing at the back, compared to one hundred forty-two previously, to space out the flanges and stiffen the wheel. The Optimiz adapter allows a non-Boost hub to be fitted into a Boost frame.

Dynamo hub and Center Lock mount

The dynamo hub houses a small alternator in the front wheel: magnets and winding generate, while riding, the current for a six-volt and three-watt lighting system, which is standard on city and touring bikes. The Shimano model presented here features a brake disc with Center Lock, the brand's fitting that replaces six screws with notches and a central nut. Before choosing a hub, the number of holes, matching that of the rim, the frame or fork spacing, and the type of axle, whether through or quick release must be checked.

Great deals

Good deals can also be found in great deals, promotions, clearance, sales, Black Friday. The new arrivals showcase the latest collections, and items shipped in 24h are prepared and shipped within 24 hours. The year's highlights follow a stable order: Black Friday at the end of autumn, the end-of-year holidays, the winter sales, the French Days of spring, followed by summer sales and back-to-school.

Frequently asked questions

Is an internal gear hub suitable for an electric bike?

City electric bikes with a central motor often come equipped with them. Check the compatibility indicated by the manufacturer, as the motor's torque heavily stresses the mechanism, and reduce pressure on the pedals when changing gears.

How many holes should a hub have?

Exactly the same as the rim: thirty-two and thirty-six are the most common in city and MTB, while twenty-four or twenty-eight are found on many road wheels. More holes make the wheel stronger, at the cost of a bit more weight.

How do you adjust a Shimano Nexus hub?

Most adjustments are made via the cable: on an Nexus with eight speeds, you engage the fourth gear and align the two visible yellow markers on the mechanism. An overhaul with internal lubrication should be handled by a workshop.

What does the number of engagement points on a rear hub indicate?

It shows how many times per turn the freewheel body can engage. The higher this number, the more responsive the transmission is to pedalling, an advantage in technical MTB sections.

How can you identify a Boost hub?

Measure the spacing between the frame or fork's arms: one hundred forty-eight millimetres at the rear and one hundred ten at the front indicate Boost, compared to one hundred forty-two and one hundred for the old through-axle standard.