Start from cold and check the exhaust temps on all 4 cylinders right at the heads. Make sure they’re running close to each other. They run surprisingly strong on three cylinders. If you have a cold pipe start looking at the corresponding coil, plug wire, and the carbs again. These carbs can be finicky to get right sometimes but once they’re there keep good fuel in it and don’t let it set with ethanol in it. And yes they are a blast to ride and very comfortable bikes.