100% the issue is too much air. get your carb checked, reduce air intake.
open the air intake on the carb about 4 full turns then start the bike. if it does not want to start open the idle bring it up at least 5 turns. when it start at a very high rev, start closing the air intake slowly until you feel and hear you have hit the right spot. adjust your idle in the process.
NOTE: missfires may also be caused by a fouled out sparks
Answers & Comments
100% the issue is too much air. get your carb checked, reduce air intake.
open the air intake on the carb about 4 full turns then start the bike. if it does not want to start open the idle bring it up at least 5 turns. when it start at a very high rev, start closing the air intake slowly until you feel and hear you have hit the right spot. adjust your idle in the process.
NOTE: missfires may also be caused by a fouled out sparks