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Choosing which indoor cycling bike will meet your needs isn’t an easy decision. There are lots of things to think about if you want to make sure you get the right bike. One of the things that you should be taking into account is the bike’s Q factor.
The Q factor makes a difference to how efficient your bike is and also how similar it is to riding a real bike. It’s definitely not the only thing that you should think about when you’re deciding which indoor bike to buy, but it is an important element to consider before you make your final choice.
This guide will help you to understand what exactly the Q factor is, why it makes a difference, and how you can know which is the best Q factor for your needs.
Table of Contents
What Is the Q Factor on an Indoor Bike?
Put simply the Q factor on a bike is the distance between the pedals. The measure helps to determine how comfortable you would be on the bike and can also make a difference in whether riding the bike feels like riding a bike outdoors. There are four main measurements that are used as Q factors, and it’s generally thought that a narrower Q factor is better.
Why Is the Q Factor Important?
The Q factor of an indoor bike is important because it affects comfort and it can make the difference between a genuine riding experience and one that doesn’t feel like a real bike ride. As well as affecting comfort, it also matters when it comes to efficiency.
The right Q factor can help to make your ride more efficient and allow you to apply more pressure to the pedals. While research has shown that a narrower Q factor is usually more ergonomically efficient, it could be that a wider Q factor is better for some people. For example, it could be better for people who have wider hips.
For people who are using their bikes casually, the Q factor might not make a lot of difference. However, if you are planning to use your bike multiple times a week, that’s when you might start to notice the effects that the Q factor could have.
Q factor could be even more important for anyone riding competitively or training intensively.
Different Q Factor Sizes - Their Pros and Cons
Each Q factor can offer advantages and disadvantages. Some may be regarded as too narrow and some as too wide, while others offer a more comfortable ride. When you’re looking at indoor bikes to buy for your home, it’s worth looking at the Q factor and considering where it falls on the scale.
You can take a look at the Q factor on individual bikes to see which ones are in your desired range. If you’re not sure what might be right for you, trying out a few bikes can also be useful, if possible.
Very Narrow Q Factor - Between 110mm and 140mm
While the general opinion from experts is that the Q factor should be narrow to provide maximum efficiency, there is also such a thing as too narrow.
If the Q factor is too narrow, it could cause problems with the positioning of your legs. If your legs aren’t in the position that they should be in, it might lead to issues with your joints. On top of that, it could make you faster at first but then cause your speed to drop off as you keep cycling.
At around 110mm to 140mm, you’re likely to find that the Q factor is too narrow. However, not many indoor bikes fall into this range. You’re likely to find a wider Q factor on most bikes, which are a much more comfortable fit.
Narrow Q Factor - Between 140mm and 170mm
This range of width for a Q factor is still narrow but it doesn’t enter the realm of extreme narrowness. In fact, for most people, it’s going to be the ideal width to help you to get the most from your indoor bike. For riders with a standard human anatomy, you can enjoy efficiency when riding your bike and it will feel more like a road bike too.
This width will prevent your knees from pointing inward but it doesn’t move your legs so far apart that it’s uncomfortable or makes your cycling less efficient.
Wide Q Factor - Between 170mm and 140mm
A wider Q factor can be a good choice for some people. If the narrower range of Q factors isn’t suitable for you for some reason, going a little wider could work out. You might be very tall or have wide hips, which could mean that a narrow Q factor is less efficient and less comfortable for you.
This slightly wide range isn’t wide enough that it will prevent the bike from being efficient, but it is too wide for many people and can make cycling feel uncomfortable. You’ll be in the minority if you find this range more comfortable, but it’s possible that it’s the best option for your body shape.
Very Wide Q Factor - Above 210mm
Some indoor bikes will have an even wider Q factor of more than 21cm. This larger width is unlikely to be suitable for anyone and will most likely not be very comfortable. The majority of people are not going to find this size a good fit and it’s often found on indoor bikes that are cheaper and not great quality.
As well as feeling uncomfortable, it’s going to make your cycling less efficient, and it could even lead to joint pain or other injuries if you use the bike regularly.
How Do You Choose a Q Factor?
When you’re looking for the right Q factor for your indoor bike, there are a few things to think about. First of all, there’s the right range for your build.
For most people, a Q factor between 140mm and 170mm is going to be the optimal choice.
If you’re testing out bikes, start with a Q factor of this size and see how it works out for you. If you feel like it’s not the most comfortable option, you might then want to try out a bike with a slightly wider Q factor to see if it suits you better. However, it’s most likely that you’re going to be satisfied with a Q factor that’s narrow but not too narrow unless you have very long legs or perhaps wide hips.
But how can you find out the Q factor of a indoor bike? This is important to know first so that you’re aware of what you’re going to get.
The good news is that you shouldn’t need to take this measurement yourself. It should be available from the manufacturer, either in the bike’s manual, on the website, or in other official documentation. If you do need to measure it yourself, you only need to measure the distance between the inside of the pedal attachments on the crank arms. This should give you your Q factor so you know if it’s right for you.
Can You Modify a Bike's Q Factor?
Modifying a bike’s Q factor is possible, but only in one direction. You can make the Q factor wider, but it’s not possible to make it narrower.
If you want to make it wider, you can use pedal extenders to create more distance between the pedals. So if you’ve bought a indoor bike with a narrow Q factor but you’re one of the few people for whom a narrow Q factor isn’t suitable, you could fix it and make the bike more comfortable.
While Q factor may seem a little complicated at first, there actually isn’t too much to it. Most people are going to be comfortable and cycle more efficiently with a Q factor that’s in a similar range. Only a few people are going to want a wider or perhaps a narrower Q factor on their indoor bike to meet their needs.