hi still havent decided on engine yet what is the difference in a r1 engine and a thunderrace engine as they both have the same engine code yzf 1000 does the r1 just have a different ecu set up

Practically nothing in common between the two. The R1 was groundbreaking motor with all new technology.

They were obviously so busy developing it that they didn't have time to choose a new name for the bike.

oh well just a thought