How to adapt a ‘dumb’ trainer for virtual riding
Contributed by Claude Paré
As the outdoor season comes to an end many riders are looking at extending their season with indoor cycling. The popularity of online cycling software has made it fun and easy to join others or to train by yourself in an interactive cycling environment. This article focuses on how to use your old indoor trainer to connect to the world of online cycling.
There are two types of trainers that can be used with online cycling software: the classic “dumb” trainer and the more technologically advanced “smart trainer”.
What is a smart trainer? A smart trainer is any trainer where the resistance can be controlled by software. A dumb trainer can be described as one where the resistance is controlled manually.
Having a dumb trainer doesn’t mean you can’t use online cycling software to ride with your friends. What it does mean is that you won’t feel a change in resistance as the terrain changes. Online cycling software uses power output to calculate your speed based on the virtual terrain. A dumb trainer can only estimate your power using your speed as an input while a smart trainer can directly measure your power output and modify the resistance. Since the software cannot change the resistance on a dumb trainer, it modifies the speed calculated by the software to simulate the change in speed you encounter while riding on a changing terrain and allows you to be in sync with other riders.
Making your dumb trainer smarter
So how can you use an old-style dumb trainer on an online cycling platform? In order to register power and calculate speed, the software needs to receive data wirelessly from sensors on your bike via either ANT+ or Bluetooth protocols so you need an ANT+ or Bluetooth enabled speed sensor. Adding an ANT+ or Bluetooth cadence sensor and heart rate monitor will display more information but is not essential. Most newer sensors support both Bluetooth and ANT+ while older ones might only support ANT+. Finally, some are proprietary and will only connect with the head unit, often called the “bike computer”, and therefore will not work for online cycling. If you have a Garmin or similar sensors that transmit data via ANT+ or Bluetooth as well as a dumb trainer, you are pretty much good to go. Sensors for speed or optional cadence are readily available at any local bike store for around $60 for either speed or cadence sensors. There are many manufacturers of sensors but the most common locally available and reputable brands are Wahooand Garmin. You bike store can help you with selection.
A final option to connect online is to use a power meter whose output measured in watts can be used directly used by the software and therefore provides the greatest accuracy. The caveat is that unless you already own one or desperately want one, the price range for power meters is similar to that of smart trainers ($600-$1,800) and you won’t get the benefits of a smart trainer. Similar to other sensors, power meters support either Bluetooth or ANT+ protocols or both.
Since the connection between your bicycle’s sensors and your computer or mobile device is established using either ANT+ or Bluetooth protocols, you will need your device, whether it is your laptop, desktop, tablet, cell phone or the newest version of Apple TV, to support either protocol. Fortunately, most new computers as well as all mobile devices have built-in Bluetooth. If you have an older computer, you can purchase an adapter called an ANT dongle to connect your ANT+ sensors to your computer’s USB port. ANT donglesare available in local bike store for around $60. All brands of dongles are similar in functions and interchangeable.
The last step is to preset your trainer’s resistance based on the online platform requirements. This only needs to be done once. If your old trainer is not in the supported trainers list of your favourite online platform, do not despair as this also can be estimated but you will once again lose accuracy.
So, if you have a bike and an old trainer, all you should need is a supported speed sensor or power meter and a computer or mobile device and you can join your friends online and enjoy year-round cycling.
Helpful resources:
If you are thinking of joining club rides on Zwift or simply want to know more about setting up for online cycling, these links to ZwiftInsider have tons of great info to get you started.
Happy roads and living rooms!