Tips for calming down a OTTB when they get into "race mode"? My boys very calm for a ex racer but on the off day he gets hot I cant calm him down.

I third. Lots and lots of work on a circle, getting him forward into the contact. My horse gets like this. She is very sensitive to machinery (starting gate?) sounds so making her so busy paying attention to me that she's forgotten all about the noises is very important.

But it's harder than it sounds, I know. Short reins, DONT PULL, and leg leg leg. Do not pull back, just keep a feel and Trot until the two of you are so bored with trotting you could just die. On a circle. The minute he puts his head up half halt and get him moving forward again.
Agreeing with Maddy, he needs extra stimulation or something he can channel his “funsies” into. On sites like Pinterest, you can find a ton of interesting flatwork or drills that will keep him on his toes.
Get his mind working. Do some circle work and get him doing anything that takes his mind off running
Join the fun and sign up to connect with our 200,000 members!