In this article, I will explain how to connect a Fuelino Proto3 to your motorcycle. Fuelino is a fuel injection controller and data logger designed for motorcycles equipped with EFI (Electronic Fuel Injection). By regulating the fuel injected in the cylinder, you can increase the power of your engine. Even if this modification is optional, if you have a stock engine, it becomes mandatory if you change some components of your motorcycle, such as exhaust pipe, camshaft, cylinder size (bore up kit), air filter and so on. Fuelino helps you to adjust the injection timing, to achieve the proper fuel air ratio which maximizes the output power of the engine, or minimizes fuel consumption. The compensation applied to the original signal timing, in %, depends on the throttle position sensor signal (if connected), and the engine rotation speed (calculated from the measured time period between 2 consecutive "start of injection" events).
First of all, let's have a look at the wiring diagram. Fuelino is connected as a "man in the middle" between the Original ECU of your motorcycle (example: Keihin on Honda CBR125R), and the fuel injector. In the most simple application, you just need to connect 4 wires:
- Battery voltage, key protected (+12V)
- Chassis ground (0V)
- Injector command input (coming from Original ECU, Fuelino input)
- Injector command output (going to the fuel injector, Fuelino output)
Optionally, Fuelino is able to use, for its control algorithms and data logging operations, additional signals, such as:
- TPS (Throttle Position Sensor) voltage
- Lambda sensor (O2 sensor) voltage
- One additional digital signal (3.3-12V = ON, 0-3.3V = OFF)
The complete installation guide on a Honda CBR125R is available at this link: Fuelino_Proto3_installation_manual_20170114. For other files, please visit the section dedicated to Fuelino. However, Fuelino application is not only limited to Honda CBR125; it can be installed on any other motorcycle equipped with Electronic Fuel Injection (1-2 injectors = 1-2 cylinders), such as: Honda CBR150R, CBR250R, Kawasaki Ninja 250R, D-Tracker, Yamaha R125, R25, Aprilia RS4 125, Piaggio Vespa, KTM Duke 125/250/390, and so on. All you need to do is to check the wiring harness of your motorcycle, in the Service Manual (you can find most of them in Internet, in PDF format), and connect standard cables (you can buy them on local electrical equipment store, or home centers), as shown in the installation manual above. Theoretically, Fuelino HW can support 2 injector inputs (and 2 injector outputs), therefore it is suitable also for motorcycles equipped with 2 cylinders engine. However, at the moment, the latest SW can handle only the interrupts of 1 injector.
If you want to try Fuelino Proto3 on your motorcycle, please contact me (dadez87-at-gmail.com). You can find me also on Facebook, and Linkedin. I can support you very easily, if you have my same motorcycle. On opposite, if you have a different one, I can help you getting the service manual, and in the installation procedure, injection timings calibration, etc. The schematics, Gerber data, Arduino software and so on, are all available to everyone. But if you find problems in manufacturing the board by yourself, please contact me and I can send you a sample, if you help me with the development of this project (Paypal donations are welcome). In case many people are interested in this project, in the future I can consider to sell the samples ("kits to mount", or "already mounted kits") on Ebay, maintaining a cheap price, so that everyone can afford it, even 16 years old young guys who want to install Fuelino on their first motorcycle.
The present Hardware and Software versions are very stable, considering that I tested them a lot, and run many kilometers on my CBR125. Moreover, since the software is Open Source, in case you find any strange behavior, or you simply want to change it a bit to better meet your needs, you can do it freely; then, just re-compile the C/C++ source code with Arduino IDE (or Atmel Studio), and flash it on your Fuelino.