Free Your Cycling Power & Cadence Data!

The Data Fitness Connector (DFC) data broadcaster is a device that allows Peloton bikes to communicate with fitness watches, head units, and apps—a feature that’s not available on stock Peloton bikes. It reads power and cadence data in realtime, through a cable connected to your bike, and broadcasts them wirelessly to nearby devices, including those built around non-Peloton platforms like Zwift and Garmin (See what products are supported). This allows you to enjoy the built-in functionality of your bike while simultaneously utilizing features and services that depend on third-party platforms.

Note: DFC is not supported for use with the upgraded Peloton Bike+ that was released in 2020.

Who Wants to Ride a Bike in Walled Garden?

Interested in the fitness data you produce? Want more control over who else has access to those data? Prefer not to be locked into a particular platform? If you have a Peloton bike, then DFC is for you.

Suppose you have a Garmin watch, for example. Using it to access your Peloton data would normally require that you:

• Sync your data data with a third-party platform like Strava,
• Translate those data to a format that Garmin can understand,
• Import the results into your Garmin account, and
• Use Garmin Connect to get them on your watch.

With DFC, those data go straight from the bike to the watch in realtime!

Play Well With Others

And what if your workout room has to satisfy the needs of a cycling enthusiast and a spinning enthusiast? Rather than buying (and rearranging furniture to accommodate) one indoor bike for Peloton and another for Zwift, you can just plug in your DFC and share a single Peloton bike. And if you get curious about some other structured training platform—The Sufferfest, for example, or Trainer Road—you’ll have everything you need to check it out.

A Starting Place for Makers & Fitness Innovators

One of our goals for this project is to make it easier for hobbyists to design and build hardware that interacts with fitness machines, which is why we’re offering the DFC Maker Edition. Sure, if you’re trying to start the next indoor fitness revolution, you probably have your own hardware team. But what if you just want to crank up the music and cue some heroic lighting when you hit your pace? Or simulate the wind in your hair by pointing a fan at your face and making it blow harder the faster you go? Or fire off some confetti when your break your distance record? DFC brings your quirky idea to life and lets you take it for a ride on the handlebars.

Or you can do something more practical…if you must. Add a dedicated display and use it to chart realtime metrics that Peloton doesn’t provide. Maybe make it an e-paper screen for better sunlight readability? Or log your raw data offline for the last word in platform independence. Or attach an array of sensors and monitor how your performance is affected air quality, humidity, and other indoor environmental factors (like confetti). It’s entirely up to you!

Features

• Wirelessly broadcasts cycling power and cadence
• Connects to apps and third-party fitness devices
• Supports two simultaneous wireless connections
• Supports wireless device firmware updates for future upgrades

Technical Specifications

• Built around the Nordic nRF52840
  • ARM Cortex-M4 32-bit processor
  • 2.4 GHz wireless transceiver
• 11 exposed GPIO pins in a breadboard- and IDC-compatible layout
  • 4 analog or digital pins
  • 7 digital-only pins
• 16 M-Bit QSPI external flash memory
• Two channels of bi-directional RS-232-to-TTL/CMOS conversion via MAX3222 IC
• I²C JST connector compatible with SparkFun's Qwiic or Adafruit STEMMA QT Connect System
• SWD connections on the front and back of the board via Tag Connect footprints
• 18 V max to 3.3 V voltage regulator
• Two 3.5 mm stereo jacks connected to one another and to the RS-232 driver/receiver IC.
  • An off-by-default jumper allows the transmission of RS-232 data through the jacks
• USB Type-C connection for power operating from 5-18 V
  • Configurable routes via solder jumper for SBU1/2

Open Hardware

DFC is open hardware. The schematic, layout files, and case design files are published on our GitHub repository. We also provide an Arduino-based reference implementation that we used for early prototyping. It supports cycling power and cadence data, and you can modify it using Arduino IDE to change the functionality of the board. An SWD programmer like the Nordic nRF52840-DK and a Tag Connect cable can be used to program it. The production Fitness Edition firmware is not open source.

Comparisons

Support & Documentation

DFC is open hardware, and you can find our documentation in our GitHub repository. If you have any questions, please reach out to us using the Ask a technical question link link on our campaign page.

FAQ

Q: Which fitness bikes and devices are compatible with DFC?

DFC was designed to be compatible with the original Peloton "Bike" and will only be supported for use with that model. Testing with the "Bike+"" has found that it’s going to be infeasible at this time to support it.

Most any device or app that supports power meters should work with DFC. For a list of devices that are known to work (or not) with DFC please see this table. Some devices like the Garmin Venu and Instinct do not support power meters from any manufacturer but do support speed sensors which DFC can act as with a firmware update.

Q: How will I connect it to the bike?

DFC has two jacks that look similar to the ones you might use to plug in headphones. You’ll unplug the data cable from the back of the bike’s display, and insert them into one of those jacks on DFC. You’ll then connect a second (provided) cable from DFC to the back of the display. It’s really simple and requires no cable-cutting or permanent modifications to the bike.

After that, you’ll be able to connect it to the platform you want to use (Zwift, Garmin, etc.) and it will works just like a power meter.

Q: How does DFC work with my fitness device?

The details here are for Garmin devices but others will be similar. Once you do the initial pairing the Garmin will connect automatically every time you start a ride. You just go to start Indoor Cycling on your watch and it all shows up.

The Garmin will start recording (if you want) before the class starts as long as the power/watts are displayed on the Peloton screen. Then, when the class is over, you can keep going with a cool down and the Garmin will keep recording your data. Another thing you can do is string a few Peloton classes together and have them show up as one workout on the Garmin.

An additional benefit is that by connecting DFC to Peloton you get the Garmin FirstBeat analytics which will give you info on training status, recovery, load, VO2 max, FTP, etc.

Q: Can DFC broadcast speed data in addition to power and cadence?

We have a prototype of this working but testing with several fitness devices revealed some undesired behavior. Some devices only pick up either power data or speed data but not both. We’re working on this and will release an update once we get it working consistently across devices.