This is a 2019 300cc gasgas that back fires on kicking any suggestions please 

Does it fire up? If not check the wudruff key or try a different spark plug..

 

When it starts it seems to run fine I've changed the plug a couple of times we bought the bike new but my lad put up with it    he now has given trials up so I've now inherited the bike and problem    could it be a faulty CDI unit thanks

When CDI went on mine, it backfired badly. Clean the pick up first as they can also rust.

Ill will try that thanks but this has been doing it from brand new the bike is only 6 month old and at most only been used 10 times 

If doing this from new might be running lean on the low end?  Maybe adjust the air/fuel setting and check what jets are in it and?

If you have had it from new could you not seek advice from the dealer ( If they are open of course ! )

Thanks for all your advice I have spoke to tony today (road and trials)he told me to check a few of the simple things first 

Like carb    done 

Spark plug      done 

Loose connection on plugs  done

I'm going to try to change my cdi unit of my 2014 if it fits and then who knows