The kids filming are speaking Thai with a heavy rural accent. Quick translation:

Kid1: mother fucker that’s cool as fuck.

Kid2: get closer get closer, step on it

Kid1: I’m stepping, I’m doin 100 (km/hr)

Kid2: not too close though cuz he probably doesn’t have insurance

Kid1: here you film. That’s cool as fuck.

Passes the driver, driver waives

Kid1: he even waives! (Laughter)