The hub is the most expensive part of a wheel and, generally, the one that lasts longest. On a damaged wheel it is almost always intact: the rim takes the impact, the spokes break. You just need to be sure before shipping anything.
Check 1 — Side play
Wheel fitted to the bike, the bike on the ground. Take the rim at the top with both hands, then push and pull it sideways, at right angles to the frame. Without forcing: a clear movement is enough.
How to read the result
- Nothing moves — the cone adjustment is correct. Good sign.
- A slight movement, without noise — often just a cone adjustment on a cup-and-cone hub. Recoverable.
- A sharp knock, or clear play — either the adjustment has drifted, or the bearings are pitted. Have it checked before sending.
Beware a classic trap: play felt at the rear wheel does not always come from the hub. First check that the axle is properly clamped in the dropouts, and that the cassette itself is tight.
Check 2 — The spin
Take the wheel out and turn the axle between thumb and forefinger. A hub in good condition turns on its own, effortlessly, perfectly evenly. What you are looking for are the faults the hand detects far better than the eye:
- a gritty feel, like sand under the fingers;
- hard spots that come back on every turn;
- a general resistance, although nothing is rubbing.
Complete it by ear: wheel in the air, spin it and listen close to the hub. A healthy bearing makes a continuous, muffled sound. A squeal, a metallic rasp or an irregular clicking betray a damaged bearing race.
Too tight is a fault too
We mostly look for play, but the opposite excess exists too: a hub adjusted too tight brakes the wheel permanently and crushes its bearings. If the wheel, once removed, stops almost as soon as you spin it while nothing is rubbing, the adjustment needs revisiting.
Check 3 — The freehub body (rear wheel)
On the rear wheel, the part that carries the sprockets deserves a separate look. Two things to examine:
The splines
Remove the cassette if you can and look at the grooves of the body. On a hub that has worked hard — and particularly on aluminium bodies — the sprockets dig notches into them. Light marks are normal. Deep grooves, to the point where the cassette seats crooked, call for replacement.
The freewheel mechanism
Turn the body in the pedalling direction: it must drive firmly, without slipping. In the other direction the clicking must be regular. A body with side play relative to the hub, or that skips under load, is at the end of its life.
What can be repaired, what cannot
A cup-and-cone hub can be adjusted, cleaned and regreased: many hubs written off as beyond saving only need a service. On cartridge-bearing hubs the bearings can be replaced, which costs more but very often remains worthwhile.
On the other hand, three faults are final: a split hub shell, a flange cracked at the spoke holes — look at them closely, that is where it breaks — and a damaged thread or axle. In those cases there is no longer any base on which to build a wheel.
The special case of the motor hub
On an electric-assist hub, a fourth check is added: the power cable. Follow it along its whole visible length, from where it leaves the hub. A split sheath, a bare wire, a severed strand or a corroded connector are matters for a motor specialist, not a wheelbuilder. Have this dealt with before sending us the hub: a new wheel around a failing cable is of no use.
The two-minute summary
- Side play zero or almost zero, with no knock.
- Axle turning freely, no grit or hard spots, no metallic noise.
- Freehub body without deep notches, firm drive.
- Flanges and shell free of cracks around the holes.
- Motor hub: power cable intact along its whole length.
Those boxes ticked, the hub can take a new wheel around it.
Before shipping it
We build around what we receive: checking beforehand saves you a pointless round trip. Three reminders, taken from the order form:
- The hub alone, removed. A complete wheel, or one partly stripped, means a dismantling charge on top.
- Aluminium and J-bend spokes only. No carbon, no straight-pull hubs.
- The completed form inside the parcel, with “Retour moyeu” marked on the shipment.
Unsure about one of the checks? A call to the workshop settles it faster than a parcel.
Why your measurements matter so much
A spoke works like a screw: it must be the right length, to the millimetre. That length is calculated from the effective rim diameter and the hub measurements — flange spacing, hole diameter, position of each flange relative to the axle. On a rear wheel, the two sides almost never take the same spoke length: the room taken by the cassette offsets the right-hand flange, and the rim would not stay centred in the frame if the same length were fitted on both sides.
That is the whole point of the order form. A diameter in inches is not enough for this calculation, and it is also why we ask for the over-locknut dimension: it is these figures, not a bike model range, that determine the build.
What the build commits us to
Lacing a wheel puts the hub under tension. On an old hub, or one that has worked hard, a flange already fatigued may give way during the operation. It is rare, but it happens, and no visual check predicts it with certainty: a crack starting between two holes stays invisible. So we cannot answer for it. That is also the reason for the flange check described above: it rules out most nasty surprises.
For motor hubs the situation is the reverse, and it should be said plainly: the build does not touch the power cable. It is neither unplugged, nor moved, nor stressed. We do not check its condition, and it cannot be damaged in our workshop. Checking it is up to you, before shipping.
Is the hub sound?
New rim, spokes and nipples, lacing then lateral true, radial true and dish set by hand. Back within 48 to 72 hours, return carriage included.
