Have had my Roadster 2010 from new, this is the first problem I have had with it! Bike won’t start, put new battery in but same result, just a click. I have full power everywhere else?
Hello Deanm and welcome from Virginia. Your battery cable may be the issue. I will assume you tightened them both when you installed the new battery. Corrosion develops just inside the leads and increases the restriction thus does not allow enough electricity to turn the OEM starter. You may need new cables as cleaning the inside of old ones is not recommended or easy.
This link show how to upgrade your starter to a Toyota/Lexus unit. I'm not mechanic and did this easily enough: Page 16 of this thread is my install with pictures Inexpensive Starter Replacement