Changing the chain on your bike is part of the regular maintenance, but knowing the right chain length is essential for the success of this operation. You can either determine the value manually or use Chain Length Calculator, an app designed specifically for this purpose.
But how hard is it to calculate the chain length? Do you really need an app for it? Let’s have a look at the various methods in detail.
How To Calculate The Chain Length Manually
Calculating the chain length manually is not too complicated. But before describing the sizing process, perhaps we should have a word about the types of chains.
Single-speed bicycles usually use a master link chain. Multi-speed bikes can be equipped either with master link or special connecting rivet chains. Master link chains use two removable plates that connect the ends of the chain together whereas rivet chains use a rivet that connects the ends of the chain and require a special tool to mount or dismantle them.
To calculate the chain length manually, you can either size the new chain to the original chain or use the largest cog and the largest chain ring method.
The first method is the simplest. Just remove the old chain and lay it on a flat surface. Stretch the new chain along the old one to determine the exact length.
While this method is simple and accurate, there are situations when the old chain has an improper length. If you’re building a new bike, you may not even have an old chain at all.
In this case, you can use the largest cog and the largest chain ring method. This process is also fairly easy. Place the chain over the largest sprocket and over the larger chain ring, then bring the ends together. At this stage, don’t route the chain through the derailleur.
Count for more chain links to the length achieved and detach all other links. This method works well on all multi-speed bikes, including recumbent road bikes, mountain bikes or commuter’s vehicles.
While both methods above are simple, if you don’t feel like measuring manually, you can use Chain Length Calculator. Here’s everything you need to know about it.
Chain Length Calculator App
Chain Length Calculator is a simple app for mobile devices that works out the recommended length of the chain based on information provided by the user. The app expresses the chain length in number of links, making it easier to determine the right length if you don’t have a ruler or meter at hand.
The app allows users to input the chainstay length either in the metric or in the imperial system; this is useful for bikes manufactured in Europe, where the metric system is more popular.
Other data required is the number of teeth on the biggest front gear and the number of teeth on the biggest rear gear. Once all data is input, the app will return the suggested chain length in number of links.
Chain Length Calculator – Pros
The main advantage of this app is its simplicity. All required data is easy to find either on the bike’s manual, on the manufacturer’s website or by counting the number of teeth on the gears. That beats the similar chain length calculators available either online or as apps.
Another great advantage is the size of the app. It occupies almost no space on the device and requires little resources.
By introducing accurate data, you’ll also get the ideal chain length for your bike. No misinterpretation and estimations. This is very helpful for those who are not confident enough on measuring the chain manually, making life easier.
Chain Length Calculator – Cons
I would have loved to say this app has no cons. And it doesn’t. As long as you own an Android device. Sadly, this tool is not available for iPhone users, although there are similar apps for iOS devices.
Chain Length Calculator is a simple, easy to use, and awesome app to consider. It helps you determine the chain length without fuss, for a quick and simple chain substitution.
What Is A Bike Chain?
If you’re new to cycling and just getting accustomed with the terms, a bike chain is the central element for propulsion. It consists of individual inner and outer plates held together by studs or bolds. There are various types of chains and what matters when choosing is the type of derailleur.
Multi-speed bikes come with 9, 10, or 11-speed derailleurs; the number indicates how many gears the derailleur can switch and it’s important because chains for 9-speed derailleurs may not fit on a 11-speed derailleur and vice versa. In fact, the chain may be wider or narrower depending on the type of the component.
Another thing to consider when choosing the chain is the type of bike. Mountain bike and road bike chains may differ in weight and stability. Some chains are even developed specifically for an improved switching performance on a determined type of bike.
Chainstay, Sprocket, Chain Ring – Why Do They Matter?
Either manually or with the help of an app, calculating the chain length requires data about these components. But why?
To start with the chainstay, this element of a bike has various lengths and it makes sense that a longer chainstay needs a longer chain. The length of the chainstay can be found either in the bike’s manual or on the manufacturer’s website. Alternatively, just measure it.
The sprocket and chain ring also matter, but you’ll only have to count the number of teeth on the biggest front and rear components. Their size matters because this is the configuration in which the chain will be pulled the tightest.
Once you’ve got these measures, it’s easy to determine the right size of the chain, either in inches or in number of links.
Why Do You Have To Change The Chain?
If maintained and lubricated correctly, the chain can last for a long time. However, a worn chain can damage the sprocket and chain ring by slowing down gear shifting. Since it’s less expensive to change just the chain, it makes sense to substitute it frequently.
When changing the chain, it is essential to determine the right size. A too loose chain will hang on the gears, having a negative impact on gear switching. A too short chain can damage the derailleur but also the largest gears, due to too much tension.
That’s why it is important to determine the correct chain length before mounting the new component. When in doubt, just install Chain Length Calculator or a similar app to help you with your measurements.