Actually, the B6 motor comes from the GSX600F Katana, but that motor is in the same family as the original GSX-R750 and GSX750F Katana.
The Bandit 400's engine is derived from the GSX-R400 (GK73A) of the same era, but power levels can vary by market. Like the 250, it is a member of the Suzuki Advanced Three-way Cooling System (SATCS) family.
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