I have a 2008 GW Trike (Independent Rear Suspension) always riding two up (420 lbs.) with 12,500 miles. I am the only owner and always use 87 octane fuel and have always got between 35 and 36 MPG consistently since it was new (I check it every time I fill the tank). Because I think 30 MPG is low, I would try Fuel System cleaner (not Fuel Injector Cleaner) accasionally, run Synthetic Oil (such as Shell Robella T6) in the crank case to improve lubricity and minimize wear friction, keep the front tire at 41 PSI and make sure the rear tires are inflated to at least 22 PSI. Your mileage seems low for a "one up" rider (5 MPG would be a 17% improvement). I am assuming that your EFI system is in good working order and has been checked by your Honda mechanic. Good Luck