Bike hub: maintenance and bearing adjustment

Two types of hubs, two approaches

There are two main families of hubs: cup-and-cone and sealed bearings (cartridge bearings). The difference is fundamental for maintenance.

Cup-and-cone (Shimano): loose balls roll between a cup (pressed into the hub shell) and a cone (threaded onto the axle). Bearing play is adjusted manually via a locknut. This is the traditional Shimano system, still used across the entire Shimano range including high-end (Dura-Ace, XTR).

Sealed bearings: standard industrial bearing cartridges (6001, 6802, 6803, 6902...) are pressed into the hub shell. No adjustment possible — when they wear out, you replace them. This is the system used by DT Swiss, Hope, Chris King, Industry Nine, etc.

When to service?

• Cup-and-cone: yearly or every 5,000 km, or as soon as you feel lateral play (the wheel wobbles when you shake it side to side)
• Sealed bearings: every 1-2 years or 10,000 km, or when rotation becomes rough (you feel notchiness when spinning the axle by hand)
• Freehub body: every 2 years or 15,000 km. Pawls and springs get gummed up

Cup-and-cone adjustment — step by step

Tools

• 2 cone wrenches (13 mm, 15 mm, or 17 mm depending on the hub — most Shimano use 15/17 mm)
• Thick grease (Shimano Premium Grease or Park Tool PolyLube)
• Clean rag

Procedure

1. Remove the wheel and take out the quick release or thru-axle
2. Non-drive side (left on a rear hub): hold the cone with a cone wrench, loosen the locknut with the other wrench
3. Remove the cone + locknut + washer from this side. Note the order!
4. Remove the axle from the opposite side. Balls will fall out — have a container ready
5. Clean everything: balls, cups, cones, axle. Inspect the cups: if you see pitting (small impact marks), the hub is at end of life
6. Count the balls: note the number per side (usually 9 balls per side on rear, 10 on front). Replace with new ones (they cost almost nothing, about 2 EUR for 50)
7. Re-grease generously the cups, replace the balls (the grease holds them in place)
8. Reassemble the axle and the cone on the non-drive side

The fine adjustment

This is the critical part. The cone must be tightened just enough so there is no lateral play, but without friction.

1. Tighten the cone by hand until it contacts the balls
2. Back off about 1/16 of a turn
3. Hold the cone with the cone wrench, tighten the locknut against it
4. Check: spin the axle — it should spin freely. Shake laterally — no play should be perceptible
5. If play persists, tighten the cone by 1/32 of a turn and recheck

Tip: on a rear hub, set a tiny deliberate play (barely perceptible). When the wheel is clamped in the frame, the axle will flex slightly and this play will disappear.

Sealed bearing replacement

Tools

• Bearing puller (Park Tool HHP-3 or universal drift)
• Bearing press (Park Tool HBP-1 or threaded rod + washers)
• Replacement bearings (exact reference — e.g., 6802-2RS for DT Swiss)

Procedure

1. Identify the bearing reference: it is stamped on the seal or in the manufacturer documentation (e.g., 6802-2RS = 15x24x5 mm)
2. Drift out the old one: insert the drift from inside the hub, tap evenly. The bearing comes out the opposite side
3. Clean the seat: check for corrosion or burrs
4. Press in the new one: use the press applying force ONLY on the outer race. Never on the seal or inner race — you would crush the balls
5. Check: the bearing should sit perfectly flush and spin freely

Freehub body service

The pawls that make the famous buzzing sound when you coast will eventually get gummed up. Symptom: the freehub slips (you pedal into nothing) or the sound has gone silent.

1. Remove the freehub body (usually a 10 or 12 mm Allen, or a specific tool)
2. Clean the pawls and springs with solvent (not WD-40 — it dilutes grease and dries out)
3. Re-lubricate with light grease or the oil specified by the manufacturer (DT Swiss uses specific service oil, not grease)
4. Reassemble and verify pawls engage properly in both directions

Need the torque spec for your thru-axle or the exact reference for your bearings? L'Atelier finds the info in your hub's technical documentation within seconds.