Shifter Cables and Adjustment Marks

Cable tension and alignment marks decide whether a cable-shifted hub lands cleanly in each gear. The setup steps differ by hub, so your maker's manual is the source for them. This page explains the parts and the terms.

The cable

A shifter cable is a type of Bowden cable. Wikipedia describes it as using the "movement of an inner cable relative to a hollow outer cable housing"¹. The inner cable moves and the outer housing stays still.

Wikipedia also notes that provision is usually made for "adjusting the cable tension using an inline hollow bolt"¹. Bike shops call that a barrel adjuster. Your hub's manual may or may not use it as part of setup.

Where the indexing lives

Indexing means the click positions that line up each gear. Wikipedia says that "Traditional hub gears are indexed at the shifter, making operation dependent on correct cable tension"². It adds that "Modern hub gear-units incorporate the indexing within the unit"².

One 14-speed hub is described as using a twist shifter "with one cable pulling in each direction", and "The indexing mechanism is part of the hub"³. So a hub may use one cable or two. Check your own.

Alignment marks

Many hubs carry some kind of mark or window that shows when the cable is set right. The details differ. Some sit on the hub, some on a small clicker box, some on the shifter. Wikipedia's articles don't describe any of these marks, so this site can't say what yours look like.

Find the page in your maker's manual that names the marks. It should show which gear to select while you set them. Follow the order it gives, and every safety step.

Wikipedia says many older-style hub gears "default to top gear at slack-cable"². It says some modern hubs, such as a 7-speed model, "default to bottom gear" instead². So a loose or broken cable can leave you in different gears on different hubs.

Why it matters

Wikipedia warns that "It is sometimes possible to select no gear when changing gears with a poorly adjusted gear cable, which results in a complete loss of drive"². The motor wouldn't help either if the hub isn't engaged.

Questions before you buy

• Is the hub cable-shifted, and does the manual show where to adjust it?
• Where are the alignment marks, and does the manual show a picture?
• Will the seller show you the manual page for setup?
• Is setup listed as a job for the owner or for a dealer?
• What does the cable path look like from the shifter to the hub?

If the maker's page is hard to find, ask for it before you pay.