Radiator fan

[Gnasher]

As said the bike has a very efficient cooling system and it does take a lot to get hot enough for the fan to come on, something like 15mins of idle on a warm day.  You've tested the fan and it works, have you tried 15mins or so of idle?  If your that worried, you can test the thermo switch, you need to remove it and do a hot water pan test.