Hi all, I'm new here and I've got a Super 8 125 that backfires in the exhaust during deceleration especially from higher speeds (say,70-90kmh). They are really loud POPS, like gunshots and its scaring the hell out of my wife(and me too!!!),who rides piliion with me in the mornings to work. I've notice that it happens during sudden roll-off deceleration from speed. If I roll-off the throttle gently,it does not happen, so I've had to change the way I throttle off (gently) to avoid the "gunshots" but not when I need to panic brake.... My scoot is almost 3 yrs old now and has only done about 19900km (mostly to and from work, about 28km per day). I live in a tropical & humid country with lotsa traffic. I have recently checked & adjusted the valve clearances to 0.004 for both valves and removed the carb.to clean it with carb. spray (removed both the jets but did not remove the fuel mixture screw...). It hasn't been performing like it used to since a couple of months back(poor pick-up and hesitation while reapplying throttle at speed...),which prompted me to check the valves & clean the carb.in the first place, but now its the backfiring tat's giving me a headache. I've been tinkering with the fuel mixture screw (screwing it in and out,.BTW,which way enriches the mixture? In or out?)without much help.Went back to the scooter shop & the mech.told me its the secondary air injection unit that's causing the backfiring & tat I should remove it. Is he right? Should I let him do it or can I do it myself or is it something else instead?