Chinese BBD Knockoff...?

I was playing with it today, the Chinese carb is unresponsive to idle adjustments I recommended he rebuild his Carter but I think the guy is going to buy another$ 80 Chinese knock off BBD. The oil level is dead on, oil clean no gas smell...The guy doesn't want to do the rebuild for some reason....He did say he had a fire, backfired through the carb and something may have messed up inside the carb.I do know he blew the muffler up...does Woodruff carburetor rebuid BBD's...?