Am I missing something but is it not possible to chat after a race is over.. I don't multi much but in the cool down lap the chat wasn't working. Seems like a useful feature to have.. Not really much use during a race.
Well, as soon as the leader finishes his last lap, and the 'end of race' timer starts counting down... you can still use the chat while this is happening. As soon as that timer counts down and the game goes to the results screen or asks you if you want to continue to the next session, you cannot use the chat anymore. Otherwise, no, there isnt a robust post race chat system or a race lobby chat system.
Next problem: is it my setup or is it usual that after the race text chat is partially hidden behind the "race finish" bar?