Sounds like to me you need to lean it out. All so what blend Sidewinder are you running? If you are running the Basher blend it has WAY too much oil content. I do not like Sidewinder because of all the yellowiest brown gunk that is left in the engine. Do not tune to any given temperature but for performance and then check the temp to see if it is in a safe range of 210 to 280. Keep in mind running to cool is just as bad on and engine as running to hot.