I personally don't know why the first thing on everybody's to-do list is to rip out the governor. In stock form most of these engines aren't balanced well enough to handle the higher RPM's, the heads don't flow well enough and the valve-train can't handle it. What people don't understand is once you start altering one aspect, the next weakest point is where it will fail. If you want a little more performance, up the compression by using a thinner head gasket or mill it some, clean up the ports/valve bowls, install a little stronger valve springs, a lighter flywheel, hotter coil, a 22mm Chikuni, a cheap tach/hour meter and adjust the governor around 5,000 RPM by moving the spring out on the governor arm. The result will be a snappier throttle, less valve float and better reliability without breaking the bank. This is my personal opinion, you can do what you want, either way, don't blame me if you blow up your engine.