Skip to content
Top Customer Reviews
Free Shipping & Returns*
Specialist Workshop Near You
Top Customer Reviews
Free Shipping & Returns*
Specialist Workshop Near You

Q-factor

Fahrradtechnik

The Q-factor is a measure of the width of the pedal spacing on a bicycle. It refers to the horizontal distance between the crank arms that support the pedals. The further apart the cranks are, the higher the Q-factor.

Properties of the Q-factor

A lower Q-factor generally means better ergonomics, as a narrower pedal spacing allows for a more natural pedaling technique and can result in less strain on the knee joints. A higher Q-factor, on the other hand, can result in greater strain on the knee joints and make cycling more uncomfortable.

The Q-factor is also an important factor when choosing cycling shoes. Most cycling shoes have a sole width that is tuned to a specific Q-factor to ensure optimal power transfer to the pedals.

The Q-factor varies depending on the type and model of bike. Mountain bikes usually have a higher Q-factor than road bikes because they have wider tires and a higher Q-factor allows for better handling on technical trails.

The term was coined by cycling author Grant Petersen in 1990 and has since become a recognized measurement.

Effects of the Q factor

The Q-factor can also affect cycling in several ways:

  1. Ergonomics : A lower Q-factor can lead to better ergonomics, as a narrower pedal spacing allows for a more natural pedaling technique and can result in less strain on the knee joints. A higher Q-factor, on the other hand, can lead to greater strain on the knee joints and make cycling more uncomfortable.
  2. Efficiency : A lower Q-factor can also lead to higher efficiency as it allows for better power transfer to the pedals. A higher Q-factor can allow the crank arms to be further apart, which can lead to a less favourable leverage ratio and higher energy loss.
  3. Stability : However, a higher Q-factor can lead to greater stability, especially on mountain bikes. A higher Q-factor means the feet are further apart, which can lead to better balance and control of the bike on technical trails.

Overall, an optimal Q-factor can be different for each cyclist, depending on individual body size, pedaling technique and preferred riding style. It is important to adjust the Q-factor to individual needs and preferences when selecting a bike or when customizing the existing bike.

Upside-down fork
Entfaltung Smooth Welding Heated grips

Published: March 1, 2023  |  Updated: January 2, 2026

Lisboa Triathlonrad - myvelo.de
Road bike

Lisboa triathlon bike

€7.499,00
€7.499,00
€7.499,00 - €7.499,00
€7.499,00
€7.499,00 - €7.499,00
VAT included.
 incl. FREE shipping & free returns
7-14 days delivery time
Jetzt entdecken
  • Fahrradwerkstatt zu Hause einrichten: So gelingt der Einstieg

    Fahrradwerkstatt zu Hause einrichten: So gelingt der Einstieg

    Wer sein Fahrrad online kauft, übernimmt gleichzeitig eine gewisse Eigenverantwortung für Wartung und Pflege. Das ist kein Nachteil - im Gegenteil: Wer grundlegende Arbeiten selbst erledigt, spart nicht nur Geld, sondern versteht sein Rad besser und kann Verschleiß frühzeitig erkennen. Eine gut eingerichtete Heimwerkstatt macht den Unterschied zwischen einem Rad, das ewig läuft, und einem, das früher als nötig in die Werkstatt muss.

  • Stadtradeln

    Stadtradeln: Gemeinsam Kilometer sammeln, CO₂ sparen – und wirklich etwas bewegen

    Drei Wochen lang so viel radeln wie möglich – und damit nicht nur eigene Kilometer sammeln, sondern gleichzeitig CO₂ einsparen, Kommunalpolitik beeinflussen und Teil einer der größten Fahrrad-Kampagnen Deutschlands sein. Das ist die Idee hinter Stadtradeln. Ob du Gelegenheitsradler oder Alltagspendler bist, ob du auf einem Citybike oder einem E-Bike unterwegs bist – Stadtradeln macht jeden Kilometer zählbar.

  • Per Update Drehmoment erhöhen

    Increase torque via update - how far can an e-bike motor be pushed by software?

    More torque via app update: What sounded like futuristic music just a few years ago has become a reality for modern e-bikes. For e-bikes with the Bosch BDU38 drive system, the maximum torque can now be configured via software to up to 120 Nm. The update is installed "Over the Air" (OTA) via a smartphone app - without a workshop visit, without new hardware.

See more

Häufige Fragen about Q-factor

Die häufigsten Fragen und Antworten

The Q-factor impacts ergonomics and pedaling efficiency. What is considered "good" depends on several factors, including the type of bike and the rider's anatomy.

Here are some general guidelines:

racing bikes:

Typical Q-factor: Between 145 mm and 150 mm.

Why: A narrow Q-factor is often considered more efficient because it allows for a more direct power transfer and promotes a natural pedal motion, which is beneficial for long rides and high speeds.
Mountain bikes (MTB):

Typical Q-factor: Between 170 mm and 180 mm.

Why: A wider Q-factor can provide more stability and control over uneven terrain. Also, the wider tires and frame often require a wider crank arm spacing.
Touring and travel bikes:

Typical Q-factor: Between 155 mm and 170 mm.

Why: A balance between comfort and efficiency is important here, especially for long distances and carrying luggage.
City and everyday bikes:

Typical Q-factor: Variable, often between 150 mm and 170 mm.

Why: Comfort and ergonomics are more important here, as these bikes are often designed for shorter distances and everyday use.


Individual adjustments:
Leg length and hip width: People with wider hips or longer legs might prefer a slightly wider Q-factor, while people with narrower hips or shorter legs might find a narrower Q-factor more comfortable.

Driving style and preferences: Some drivers prefer certain Q-factors due to their driving style or personal preferences.

There is no "one true" Q-factor that is optimal for all bikes and riders. The choice of Q-factor should be based on the specific bike type, the rider's anatomy and individual preferences. A bike fitting at a specialist dealer can help determine the optimal Q-factor for your needs.

Measuring the Q-factor on your bike is relatively easy and only requires a ruler or tape measure. The Q-factor is the horizontal distance between the outer sides of the crank arms at the bottom bracket spindle. Here are the steps to measure it:

Steps to measure the Q factor:

Preparation:

Make sure the bike is on a level surface and stable.

It is helpful to secure the bike in a bike stand to prevent it from tipping over.

Position the crank arms:

Position the crank arms horizontally so that they are parallel to the ground.

Measure the outside width:

Take a ruler or tape measure and measure the distance between the outer sides of the two crank arms at the widest point.

Make sure the tape measure or ruler is held straight and not at an angle to ensure accurate measurement.

Note the value:

The measured distance in millimeters (mm) is the Q-factor of your bike.

Tips:

  • It may be helpful to ask a friend for help to make sure the tape measure is held straight.
  • If your bike has wide pedals or other attachments on the crank arms, make sure you measure the crank arms themselves and not the attachments.