Start with the obvious and change the air filter (if you didn't change that already)
then ad some fuel additive to clean the carbs.
still no good ?
run the carbs without filter and put your hand on carb throat #1 whack the throttle a few times.
repeat for the other carbs.
idea is to suck debri through the jets violently.
jets are calibrated screws with(tiny) holes that regulate fuel and air flow inside the carb, they can clog up with debri.
BTW you didn't change to colder sparkplugs did you ?
then ad some fuel additive to clean the carbs.
still no good ?
run the carbs without filter and put your hand on carb throat #1 whack the throttle a few times.
repeat for the other carbs.
idea is to suck debri through the jets violently.
jets are calibrated screws with(tiny) holes that regulate fuel and air flow inside the carb, they can clog up with debri.
BTW you didn't change to colder sparkplugs did you ?