Formula

The spoke length formula used by the Rayons app has a set of limitations based the formula used and on the nature of the drawings. The formula was designed for use on conventionally laced wheels with j-bend spokes. These types of wheels are most commonly custom made by hand. The limitations outlined here may not be all inclusive.

A wheel has:

  • An even number of spokes

  • The same number of spokes on each side of the wheel

  • Equal spacing between spoke holes, on the rim or the hub

  • Spokes that are crossed in pairs on each side of the wheel which dictates a spoke count divisible by four

Minimum and Maximum Dimensions

The Rayons app can be used to calculate spoke lengths for a variety of component types. This covers the majority of Road, Track, Mountain Bike, Touring, Tandem, Downhill, Fat Bike, Generator and Internally Geared wheels. At this time, the app is not recommended for use with E-Bike components. Check your component dimensions carefully and compare them with this chart. Be sure the component dimensions are supported by the app. Read the Terms of Service for more information.

All of the values are in millimeters.

  • Front Hub Flange Diameter Minimum: 28
  • Front Hub Flange Diameter Maximum: 150
  • Front Hub Offset Minimum: 15
  • Front Hub Offset Maximum: 48
  • Rear Hub Flange Diameter Minimum: 35
  • Rear Hub Flange Diameter Maximum: 150
  • Rear Hub Left Offset Minimum: 20
  • Rear Hub Left Offset Maximum: 60
  • Rear Hub Right Offset Minimum: 10
  • Rear Hub Right Offset Maximum: 52
  • Hub Spoke Hole Diameter Minimum: 1.5
  • Hub Spoke Hole Diameter Maximum: 3.0
  • Effective Rim Diameter (ERD) Minimum: 300
  • Effective Rim Diameter (ERD) Maximum: 700
  • Rim Spoke Offset Minimum: 0.0
  • Rim Spoke Offset Maximum: 5.0
  • Fat Bike Rim Spoke Offset Minimum: 0.0
  • Fat Bike Rim Spoke Offset Maximum: 20.0

Minimum and Minimum Counts

  • Minimum Number of Spokes: 12
  • Maximum Number of Spokes: 48
  • Minimum Number of Crosses: 0
  • Maximum Number of Crosses: 4

Flange Diameters and Flange Offsets

The Rayons app is able to handle differing dimensions for the left or right Flange Diameter or Flange Offset. Controls for handling this feature are hidden until required. Read the FAQS for more detail.