A 50:1 mix is more commonly used in older air cooled motors.
With the watercooled motors, the 80:1 ratio with high quality oil seems the standard now, although some may argue to a point. Fact is, many who do not ride really hard have successfully run at 100:1 for years now without problem.
If you have ridden your bike for a length of time at that ratio. the muff is bound to be full of oil. They can clog up badly and the sherco muff is not easily cleaned(another story).
What I normally recommend is a good hard run down the road a bit through the gears, like a drag race. Done about a half dozen times will get the exhaust REALLY warmed up, and chances are it may light off some of the oil and start smoking like a freight train, just billowing, that is the excess buildup!
Let it cool down and try it again! When the excess ig is gone, it will stop that! After that, only a periodic hard run or a tough trial with some good long uphills will keep things from excess buildup. And if you are a young lad just putting about a lot and never really revving the crap out of it, you may well consider the higher ratios even. Put this way, if the pros can run 80:1 you should be just fine.
Bar end plugs help keep your bike from blowing up when you fall on the throttle side!