A slight turn of the carb mixture screws can have a big effect on your saws operation. That can be either good or bad. Buy a tachometer if you are serious about working on your own saws and especially getting into modifying them. A lot of guys here tune by ear. First you have to know what you are supposed to be hearing. Madsen's had a sound wav file that you could down load. This was to give you a sense of what a properly tuned saw was supposed to sound like. The web site is currently being revamped thus you can not access the file at the moment. My hearing isn't quite was it used to be so I just use the tach.
Hey Urbicide not sure if you are aware I called Madsens the other day when I was looking for the Threadserts to fix my 066 stripped threads and their website was down and they said it was down for good as far as they knew???