Sx 200 backfire

Noticed last year on a couple of runs I could go about 5 to 10 miles running ok then it would loose power and backfire then take off again.
Once the engine would not stop revving till i switched it off then ran ok again on restart.
Is it down to cdi problems or carb or fuel flow.
I Stripped the carb last year cleaned and checked jets but still played up before wrapping it up for winter. Be nice to sort it ready for when we can get out again.
Once the engine would not stop revving till i switched it off then ran ok again on restart.
Is it down to cdi problems or carb or fuel flow.
I Stripped the carb last year cleaned and checked jets but still played up before wrapping it up for winter. Be nice to sort it ready for when we can get out again.