Wheel Dishing Tools

What is wheel dish, and why does it matter?

A rear hub has to fit a cassette on one side, so the flanges are not evenly spaced within the axle — the spokes on the drive side sit at a shallower angle and pull harder. Dish is the act of building the rim to sit centrally between the locknuts despite that. Get it wrong and the wheel runs perfectly true in the stand but sits off-centre in the frame, so the brake rubs on one side and the bike tracks oddly. Front wheels with disc brakes have the same problem in milder form.

How do I use a dishing tool?

Set the two feet on the rim, wind the pointer out until it just touches the axle end, then lift the gauge off, turn the wheel over and put it back on the same rim without changing the setting. If the pointer touches the axle again, the wheel is centred; if there is a gap, the error is half that gap, since flipping doubles it. It is a comparison rather than an absolute measurement, which is why a slightly worn gauge can still be perfectly usable.

Dishing tool or truing stand?

A truing stand measures the rim against itself and cannot vouch for its own symmetry; the dishing gauge references the axle directly and settles the question independently. Builders who own only a stand often check dish by flipping the wheel in the stand, which works but assumes the stand's arms are true. Both sit under wheel building alongside the wrenches you will need to correct any error you find.

What should I check when buying one used?

Lay the tool face down on a flat surface — a worktop, a pane of glass — and check both feet and the frame contact it without rocking, because a bar bent by a drop puts a constant error into every wheel you build with it. Work the pointer through its full travel: it should slide without catching and lock without creeping when you tighten it, and the thumbscrew thread should not be stripped. Alloy gauges bend without any visible mark, so the confirming test is to measure a wheel you know is correctly dished and check it reads the same both ways round.

What is a used dishing gauge worth?

There are no bearings, no electronics and nothing to consume, so a straight gauge with a working pointer does the job as well as a new one and should be priced well below new. A bent one is worth nothing regardless of brand, because straightening it accurately is harder than replacing it. Buy new if you are building a lot of wheels and want the wider models that span everything from a 16in wheel up to a 29er without swapping the feet, and consider the nipple drivers listings while you are assembling the rest of the kit.