AMA/ATVA Extreme Dirt Track TT race round 2 at Sikeston, MO, was at least 6 TRX250Rs there racing with one having a KX500 engine in the frame.
Billy Clayton, Sikeston Race Park owner, owned the KX500 powered one & had long time Pro rider Jackie Medows piloting it.

Who said the 2 stroke or 250R is dieing out, NOT, but I can tell you one thing is, MONEY to keep them 4 pokers running.

Neil