Will a atc 250r motor fit in 200x frame?

No, an ATC 250R motor will not fit in a 200X frame. The ATC 250R is a two-stroke engine, while the 200X is a four-stroke engine. The two engines have different mounting configurations, and the 200X frame is not designed to accommodate the 250R motor. Additionally, the 250R motor is significantly more powerful than the 200X motor, and the 200X frame would not be able to handle the increased power.