FIT GUIDE: MEASURING STEERER TUBE AND HEAD TUBE

Aktualisiert 05.04.2022

Schritte 2

Werkzeuge 1

Ersatzteile 0

You do not know which headset version you need? We have compiled a small How-To for you, how you measure your steerer tube and head tube of your frame correctly and which headset version fits.

Werkzeuge

Caliper

Vorbereitungen

1 Disassemble the fork from the frame.
2 Disassemble existing headset.

Schritt 1: Determine steerer tube diameter

1.  Measure the upper diameter of the steerer tube.

2.  Measure the lower diameter of the steerer tube directly above the fork crown.

There are several types of steerer tube:

  • Straight 1 1/8 inch (28.6 mm) steerer with 30 mm cone seat

  • Conical steerer with 1 1/8 inch diameter top and 1.5 inch bottom with 40 mm cone seat

  • Conical steerer with 1.5 inch (38.1 mm) diameter top and 1.8 inch (45.7 mm) bottom with 47 mm cone seat. This dimension is relatively new and can still be found at few manufacturers. Time will tell if this dimension will catch on or disappear again.

  • Straight 1.5 inch (38.1 mm) steerer with 40 mm taper seat. These steerers were widespread in the early 2000s, but now these are rather rarities and not very common.

  • 1 inch steerer: Actually only occurs on bikes from the 90s and city bikes. In the MTB area not widespread.

The diameter of the cone seat is decisive for the selection of the lower eccentric of the Virtual Pivot Headset. For a fork with 1 1/8 inch steerer tube, the lower eccentric must be selected with 30 mm. For a tapered fork with 1 1/8 - 1.5 inch steerer tube, the 40 mm eccentric must be selected. In addition, a fork with tapered shaft always requires an external lower bearing cup, since the larger lower ball bearing can no longer be put in the head tube.

An overview of all available versions of the Virtual Pivot headset can be found here.

Schritt 2: Steuerrohrdurchmesser bestimmen

1.  Measure the upper and lower diameter of your head tube.

There are many different head tube diameters. The following have become established for modern mountain bikes:

  • Upper head tube diameter: 44, 49 or 56 mm

  • Lower head tube diameter: 49 or 56 mm

An overview of all available versions of the Virtual Pivot headset can be found here.