Will a 1990 750 gsxr engine fit into a 1997 gsxr 600 frame?

A 1990 GSX-R 750 engine may physically fit into a 1997 GSX-R 600 frame, but significant modifications are likely necessary for mounting and compatibility with the electrical system, cooling, and exhaust. Additionally, the 750 engine is larger and heavier, which could affect the bike's handling and balance. It's essential to consider factors like wiring harness compatibility and the overall structural integrity of the frame when attempting such a swap. Always consult with a professional mechanic or bike specialist for detailed guidance on custom builds.