it do happens here in my place.mixing kerosene on premium gas.one time i thought my mc has a problem (performance wise) so i check it out.went almost crazy trying to figure out what happened to my bike.good thing my friend ask me if i did fill up gas on that station.only then i realized it.as soon as i drain my tank and fill it up with gas fom a reputable station my bike goes like a monster again.lesson learned hehe