The ECU part number is used by the WRT software to ensure that only compatible bin files are written to that ECU.  Sometimes we do not know the ECU part number but there are several methods of finding this out.

Some ECUs have the part number written on the outside of the casing, this is useful if you are able to visually inspect the unit.

Keihin ECU showing part number on label (38770-MKP-AP2)

If you can't find the part number written on the ECU but know the year and model of a bike, you can connect to the ECU using the WRT software.  To do this first you need to open a new bin file for the same model and year and select one of the existing ECU part numbers from the list.  Don't worry if it is not identical to your ECU part number, this will be read in the next step.

First click on the 'New' button to open the Model Selector: 

In the 'Model Selector' window select your specific model (In this case a 2022 Honda CBR500R), select one of the ECU part numbers (here we have selected 38770-MKP-A01) and click on the 'New' button. 

 and use Tools > Read Part number and Serial Number. 

When the software identifies the part number, click ‘Yes’ and the software will open up that part number for you.

If this is the first time writing to a particular ECU, your PC will need to be connected to the internet for the key to be registered. After an ECU has already been flashed, you do not need to be connected to the internet to flash it. 

You can find the part numbers by using the search bar in the 'New' bin files section. This search will work no matter which part of the part number you begin with, so you can also begin by typing the second part of the part number.

  

The following video provides an overview of both of these methods: