Even at speeds approaching 3 digits, I'm still pulling 50+MPG on my '01 Katana 750 with V&H SS2R slip-on. The key is to not speed up and slow down. Once you get up to that speed, nothing's gonna chase you anyway.
That bike also has no fairings, not even a windshield, except the plastic tail section because I haven't gotten around to cutting off the subframe and adding a new one yet.
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