Headset

A typical headset service uses three Unior tools: a bearing cup press (1680/4) to seat cups square, a cup remover (1681/4) to drive old cups out from inside the head tube, and a star-nut setter (1682/4) to set the star-fangled nut at the right depth. Cone wrenches handle threaded-headset and hub adjustment.

A cup pressed even half a degree off-square makes the lower bearing run misaligned for the life of the bike. The Unior 1680/4 press pulls the cup in straight, spreading load evenly across the cup face and using mechanical advantage instead of hammer blows, so the bearing seats true.

The 1681/4 Headset Cup Remover fits 1", 1-1/8", and 1-1/4" head tubes. For larger tapered head tubes, the 1681.1/4 covers 1-1/4" to 1-1/2". Both drop a tool-steel flange through the cup, spring out behind the back skirt, and let you tap the cup out from inside the head tube.

The star-fangled nut anchors the stem top-cap bolt and sets headset bearing preload. If it sits too shallow the bolt bottoms out before preload is reached; if it sits cocked, preload never feels right. The Unior 1682/4 setter drives the star nut to the correct depth, square to the steerer, in one hammer set.

A steerer should be cut perpendicular to the tube — a crooked cut causes poor headset adjustment. The Unior 1604/2PLUS saw guide clamps the tube and guides the blade square. It fits 1", 1-1/8", 1-1/4", and 1-1/2" steerers and works with both metal and ceramic hacksaw blades.

Headset fit is defined by the SHIS standard (e.g. ZS44, EC34, IS42), which encodes the cup type and head-tube diameters. Match the press and remover tools to the head-tube measurement, not the fork. Our SHIS chart guide walks through reading the code so you order the right cups and bearings.