That being the case, don't use less than the 25 to 1 mix on
break-in. I was misinformed by BGF to use 16 to 1 which will
quickly clog your filter & diaphragm. Having spoken with others,
an hours run time varying the speed between 3000 & 7000 rpm
is all the break-in you should need. They're really loud at first,
but once some carbon builds up in the can, they quiet down
a good bit. An after market muffler is kind of a waste on a
cheap engine like this. (silk purse/sow's ear) Be sure it runs
okay for a while before investing in mods.
Scoot, if this is your 1st fric-drive, a tip. Pedal off to about
7 mph before giving it throttle & do so gradually. This will
save your clutch & your tire. What kinda of bike? What tire?