Welcome! First thing I would do is to check compression. If compression is at least 120 or so,you might want to check the carb for stopped up jets,needle and seat problems. Backfiring and loosing power on a two stroke can be a partial seizure of the piston/rings. They can continue to idle,but will not take any throttle. Have had this happen on low compression engines also. Plus slightly leaking crank seals(especially the one behind the front clutch) can cause lean fuel/air mixture problems causing it to bog. You can also check that the throttle lever doesn't have more than 1/8" slack,but don't think that is the problem.Usually they would die if there's too much slack. OPT
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2000 Chevy Silverado 1500 Sport side (272,000 miles,semi retired)
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