OP if you really want to get a bike to save fuel keep in mind the extra maintenance, insurance, cost of gear, tire replacement every 8-10k miles etc. Not saying it won't be cheaper in the long run just keep those items in mind.
If those items don't bother you and you keep your ego out of it, the search for a comfortable, cheap, fuel economy bike is answered by several manufactures making 300-400cc motorcycles. If you aren't a huge guy these bikes although not fast, are big enough to handle you. They will run 100+ MPH, get 60-70 mpg on 87 octane and cost around 5-6 grand when new. Meaning you can typically get a lightly used one around your budget. They also typically have much more comfortable ergonomics keeping you in a more upright riding position.
My first bike was a CBR250R back when they first came out, I paid $3995 brand new, it cost me $39 a month for insurance as a new rider, ran 87 octane, would hold me and a passenger just fine, and the best part was you could ring it out at redline doing relatively safe speeds all day long and still get 70 MPG. Bike was lightweight and handled pretty well, easy to flick back and forth.
Like I said if you keep your ego out of it and are ok with getting a slow bike, those small CC "sport" bikes are hard to beat. Plus they look pretty good now, much more like their big brothers than they used to. I honestly miss mine sometimes. If you want to go cruiser you can find something metric to keep cost down but you aren't going to get nearly as good of fuel mileage on any of those. Most of the good cruisers if found in that price range are in pretty bad shape. I vote if you want a good cruiser up you would have to up your budget and get something in the 7-8 range for something decent
If those items don't bother you and you keep your ego out of it, the search for a comfortable, cheap, fuel economy bike is answered by several manufactures making 300-400cc motorcycles. If you aren't a huge guy these bikes although not fast, are big enough to handle you. They will run 100+ MPH, get 60-70 mpg on 87 octane and cost around 5-6 grand when new. Meaning you can typically get a lightly used one around your budget. They also typically have much more comfortable ergonomics keeping you in a more upright riding position.
My first bike was a CBR250R back when they first came out, I paid $3995 brand new, it cost me $39 a month for insurance as a new rider, ran 87 octane, would hold me and a passenger just fine, and the best part was you could ring it out at redline doing relatively safe speeds all day long and still get 70 MPG. Bike was lightweight and handled pretty well, easy to flick back and forth.
Like I said if you keep your ego out of it and are ok with getting a slow bike, those small CC "sport" bikes are hard to beat. Plus they look pretty good now, much more like their big brothers than they used to. I honestly miss mine sometimes. If you want to go cruiser you can find something metric to keep cost down but you aren't going to get nearly as good of fuel mileage on any of those. Most of the good cruisers if found in that price range are in pretty bad shape. I vote if you want a good cruiser up you would have to up your budget and get something in the 7-8 range for something decent