The porting is a touch more "aggressive" than a standard pump gas port. The domes and timing dictate the fuel requirements more than the porting.My dad rides it and I figured a little more grunt would make it an easier ride for him to handle. So I run a little extra timing and 100LL. When I ran it on good premium pump , I backed down the timing some. But I prefer the setup on 100LL for no more than it costs over premium pump.