Picked up a 2000 blaster recently. From what I understand the engine seized up and was rebuilt, allegedly bored over 30 and P&P. Afterwards the owner swapped to twist throttle and installed a Mikuni 26 606 carb. Ever since then it's not running quite right. There a lag when you snap the throttle sometimes and it loses power (bogs) at top end. As soon as I got it I changed the fuel, cleaned the strainer and made sure my air system is clean with a new filter. Put a new spark plug in and ran it. After running around the block a few times testing it the plug is tan and looks good. Was going to clean the carb and get new Reed valves but I'm new to small engines. Does this seem like a jetting issue even though the plug looks good?