To me the ultimate adventure bike can be ridden cross country and in gnarly single track trails however no such bike currently exists. I'm picturing an ultra high performance dual sport with an engine designed for longevity, windshield, comfy seat, 200 mile range (+4 gallon tank), 3-75mph cruising speeds (extremely wide transmission), capable of holding some luggage and as light as possible (sub 300lbs). It seems easier to take a high performance dual sport and add all the comfort features than to take and adventure bike and try to get high performance. Some of best dual sports out there are the KTM 500EXC, Beta RS500, Husaburg FE570, KTM 690 Enduro, Suzuki DRZ400 and Yamaha WR250R. Each with their strong points but none having everything I'm looking for. The ones with the highest performance don't have the engines design for longevity or are high maintenance and the others are too heavy. Since there isn't anything on the market that is just what I'm looking for I have decided to build the ultimate adventure bike for me. I decided to start with an ultra high performance MX bike and I had happened to stumble across a street legal CRF450R. The chassis and suspension are superb however the motor and transmission aren't designed for the type of riding I'm looking to do so I'm going to have to do a motor swap. I decided on a Ninja 300 engine and transmission since the it's a modern motor with fuel injection, reliable, large oil capacity and a really wide ratio, 6 speed transmission. From online sources, it gets around 50mpg, cruises 80mph and tops out at 115mph ish. I just ordered a Ninja 300 engine and I hope to receive it sometime next week. The engine its self seems shorter but a little wider however I don't think it will be an issue to install. I did find stock ninja 300 controls and gauges which I plan to use. For the chassis, I ordered an IMS 4 gallon gas tank (6.6g just looked too huge) and I'm planning on ordering a Daylong seat. The windshield is still up in the air. When it's finished I'm hoping for +50mpg, 200 mile range, 270lbs with all accessories (minus gas) and ready for the gnarliest terrain.