Complex sentence: The MiG-25's speed was limited to Mach 2.83 in operations, but it could reach a maximum speed of Mach 3.2 with the risk of damaging the engines beyond repair.
Split into simpler sentences: The MiG-25's speed was limited to Mach 2.83 in operations. But it could reach a maximum speed of Mach 3.2 with the risk of damaging the engines beyond repair.