I would say that 125 is still a pretty safe temperature. But if the engine is 125 after a 5 minutes qual run, you should make it a bit richer for the finals, because you will run over 140 after 10-15 mins in the final. I am usually targeting the temp between 110 and 120, it will still run good with 100-110, but in a while your plug and head of the piston will become black