Deep-breathing engines need large airboxes

Deep-breathing engines need large airboxes, and the Suzuki Gsxr had one carefully fitted into at recess at the back of the fuel tank.
Before, it was expected that inlinefour engines would breathe through an airbox directiy behind the engine, which meant that it was ingesting air heated by the engine itself.
The Suzuki Gsxr iteration moved the airbox inlet up, away from that blast of heat.