๐ดโโ๏ธ DIY Arduino Bike Computer
Making $500+ bike computers obsolete with $20 in parts
๐ The most innovative open-source bike computer that outperforms commercial alternatives
๐ Why This Project Will Change Everything
"GPS navigators were inaccurate, expensive ones were basic... so I decided to create my own"
This isn't just another Arduino projectโit's a revolution in affordable cycling technology. While Garmin charges $300+ for basic functionality, this project delivers professional-grade bike computer features for under $20.
๐ก The Innovation That Started It All
Born from frustration with expensive, limited bike computers, this project proves that innovation beats corporation. Using a simple Hall sensor and magnet, we've created a system that's more accurate than GPS and more feature-rich than most commercial alternatives.
๐ฅ See It In Action

Real bike computer in action - smooth, professional, and completely DIY
๐ Features That Blow Commercial Computers Away
๐ Real-Time Analytics
- Instant Speed: Precise velocity measurement (m/s or km/h)
- Smart Distance Tracking: Cumulative and session distance
- Acceleration Monitoring: Real-time acceleration with max detection
- Intelligent Averaging: Separate averages for total and moving time
๐ Professional-Grade Data Visualization
- Live Velocity Graphs: 1, 3, 5, and 15-minute real-time plots
- Historical Data: EEPROM persistence across power cycles
- 8 Display Modes: Comprehensive data at your fingertips
- Smart Display Management: Auto-brightness and sleep modes
โก Smart Power & Performance
- Ultra-Low Power: Powered by any USB power bank
- Intelligent Sleep: Automatic display management
- Instant Wake: Motion-activated display
- Debounced Sensors: Rock-solid reliability in real conditions
๐ฏ Precision Engineering
- Hall Sensor Accuracy: More precise than GPS for speed/distance
- Configurable Calibration: Perfect for any wheel size
- Noise Filtering: Advanced algorithms prevent false readings
- Professional UI: Clean, readable display even in sunlight
๐ง Complete Hardware Solution

Professional wiring diagram - enterprise-level engineering made simple
๐ Bill of Materials (~$20 total)
- Arduino Uno/Nano: $5
- Hall Sensor KY-035: $2
- LCD 16x2 I2C: $4
- Push Button: $1
- Neodymium Magnet: $2
- Power Bank: $6
๐ฌ Hall Sensor Performance Data
Actual sensor output showing precision detection
โ๏ธ Installation & Setup
๐ Quick Start
-
Clone the repository:
git clone https://github.com/astrosander/arduino-speedometer.git cd arduino-speedometer -
Install required libraries:
LiquidCrystal_I2CEncButtonGyverTimer
-
Upload firmware:
- Open
firmware/Speedometr/Speedometr.inoin Arduino IDE - Configure your wheel circumference in
lenvariable - Upload to your Arduino
- Open
-
Wire according to the diagram and mount on your bike!
๐ Physical Installation
- Arduino + Power Bank: Secure to bike frame
- Hall Sensor: Mount on fork with hot glue
- Magnet: Attach to spoke
- LCD Display: Mount on handlebars for perfect visibility
๐ฎ Advanced Features
๐ฑ 8 Professional Display Modes
- Main Dashboard: Speed + Distance + Time
- Live Velocity Graph: Real-time speed visualization
- Performance Stats: Max speed + Max acceleration
- Averages: Overall and moving averages
- Time Tracking: Session and total time
- 1-Minute Graph: Short-term velocity trends
- 3-Minute Graph: Medium-term analysis
- 15-Minute Graph: Long-term performance tracking
๐ง Smart Algorithms
- Noise Filtering: Prevents false triggers from vibration
- Acceleration Limits: Filters impossible readings (unless you're an astronaut! ๐)
- Smart Averaging: Distinguishes between moving and stopped time
- Memory Management: Efficient EEPROM usage for data persistence
๐ Real-World Testing
Real installations on actual bikes - weatherproof and road-tested
โ
Tested in real cycling conditions
โ
Weatherproof installation
โ
Vibration resistant
โ
Long-term reliability proven
๐ Open Source Impact
๐ฏ Why This Matters
- Democratizes Technology: High-end bike computer features for everyone
- Educational Value: Perfect Arduino project for learning embedded systems
- Customizable: Full source code means infinite possibilities
- Community Driven: Your contributions make it better for everyone
๐ค Contributing
We welcome contributions! Whether it's:
- ๐ Bug fixes
- โจ New features
- ๐ Documentation improvements
- ๐งช Testing on different hardware
- ๐จ UI enhancements
๐ Performance Comparison
| Feature | This Project | Garmin Edge 130 ($200) | Wahoo ELEMNT ($250) |
|---|---|---|---|
| Price | $20 | $200 | $250 |
| Real-time graphs | โ 4 timeframes | โ | Basic |
| Custom firmware | โ Full access | โ | โ |
| Battery life | Days (power bank) | 15 hours | 17 hours |
| Accuracy | Hall sensor precision | GPS (ยฑ3m error) | GPS (ยฑ3m error) |
| Customization | Unlimited | Limited | Limited |
๐ Learning Value
This project is perfect for:
- ๐ฏ Arduino beginners: Well-commented, modular code
- ๐ง Hardware enthusiasts: Real-world sensor integration
- ๐ Data scientists: Algorithm development and optimization
- ๐ดโโ๏ธ Cyclists: Understanding the tech behind bike computers
- ๐จโ๐ Students: Practical embedded systems project
๐ License & Usage
This project is MIT Licensed - completely free to use, modify, and distribute.
Build it, hack it, improve it, sell it - just keep it open source! ๐
๐ Support the Project
If this project saved you hundreds of dollars and inspired your next build:
โญ Star this repository to help others discover it
๐ด Fork it and make it your own
๐ข Share it with your cycling and maker communities
๐ Report issues to help improve it
๐ก Suggest features for future versions
๐ดโโ๏ธ Happy Cycling! ๐ดโโ๏ธ
Made with ๐ by astrosander
"Innovation doesn't require a corporation - just passion and creativity"
โก Ready to build your own? The future of affordable bike computers starts here! โก