Oh that squeaking!
I get it all the time in the winter/rainy months here in Oregon...like 7-8 months of it.
In the fall I'm gonna put on some bees wax.
They make some sort of belt spray you can put on there. The last can I was looking at said re-apply every 3000 miles.
Wonder if bees wax will last longer?
Backfire you can almost entirely get rid of by tuning your idle mix screw. Mine only makes a slight "puff" when I shut her down. The occasional backfire happens when riding and pulling the throttle to hard and having that extra fuel in there....then a BOOM or a KA-POW...sounds kinda cool when it happens.
If you wanna make a nice loud backfire hold in your clutch while your doing about 30-40 and revv up your throttle a few times, let out your clutch and blip the throttle again...you should have a nice KA-POW ready for ya