Once a bike has had the ECU matched to its red key, that ECU will ONLY work with that bike. Some features of the bike (like, reportedly, the anti-theft disabling system) will not work until the bike has had the ECU mated to the red key, so any stock factory bike will have had the ECU mated to its red key and the ECU will not work on any other bike. There are, reportedly, some services that can reprogram a factory ECU, but they cost many hundreds of dollars, at least 1/2 the factory price of a new ECU.
