Positioning and geometry

Argon 18 Frames: Composite Conductors

At Argon 18, we design our bikes by breaking the frame down into eight distinct sections, each with a specific role.

As the length of the frame increases so does the length of each section. This preserves the bike’s well-balanced proportions and ensures that all our frames, regardless of size, have ideal ergonomics and flawless handling.

1. Setback

This section of the horizontal tube is important in that it allows the saddle setback to be adjusted. Setback, one of the most critical parameters in rider position, is largely determined by seat tube angle. Argon 18 chooses its seat tube angles so as to provide the ideal range of adjustment options.

2. Reach

Reach determines the effective length of the bike, the key to rider comfort and finding the ideal position.

3. Stack

Stack is the vertical distance from the bottom bracket to the top of the headtube. It plays a key role in determining rider position and, in turn, rider comfort.

4. Seat post angle

The seat post angle helps determine rider position, but also to maximize the rider’s aerodynamics and biomechanical efficiency when leaning forward. Thus, a bike with an adequate seat post angle ensures that the rider can choose the desired seat height, adjust the front/back and find the right upper-body position.

5. Chainstays/rear triangle

Two factors are taken into account when determining the ideal chainstay length:

1. How much quick handling is wanted

  • The shorter the rear triangle, the quicker the bike’s handling.
  • In order for a bike to go as fast as possible, the chainstays must be reasonably long. That’s why our bikes are always stable, even at over 55 km/h.

2. Mechanical requirements and standards, particularly those set by the manufacturer Shimano
  • For example, chainstays must be at least 405 mm long for proper derailleur functioning and accurate shifting.

6. Wheelbase

The front centre determines much of the bike’s handling and steering characteristics. A disproportionately short frame will generate an unpredictable, twitchy ride that tends to stray from the intended path. Conversely, a front triangle that is too long reduces handling.

This geometry section contributes the most to balancing the bike’s proportions because reach length, along with the headtube angle and the fork rake, determines wheelbase length.

7. Fork angle

Fork angle is the angle formed by the headtube and the ground. The smaller this angle, the quicker the bike will turn and the faster it will go when climbing. While a wider angle makes turning harder and slows the bike when climbing, it has the advantage of providing the rider with greater stability at high speeds.

8. Rake

Rake, or fork offset, is the perpendicular distance between the steerer tube and the centre of the front wheel. This distance generally ranges from 40mm and 55mm.

Stay ahead with the Argon 18 newsletter