TTS MasterTune Single Bike Kit 2000008 MasterTune-HD is a Windows-based ECM reprogramming tool specifically for use with Harley-Davidson motorcycles that utilize the diagnostic interface. MasterTune-HD also supports 2005 and later Retrofit ECM Service Modules when installed on earlier vehicles. Note: The TTS MasterTune software is compatible with Windows XP through Windows 7. Both 32- and 64-bit versions of these operating systems are supported. MasterTune-HD Features: