Hi,
Welcome to the forums.
Yes the carbs need a good cleaning. Sounds like plugged jets.
Leave the reed alone, prolly just fine.
The jets are 17.5/92.5 and will suit most any elevation w/o problems. if you want, you can put a 90 main jet in it.. The LT80 is jetted VERY fat.
The stock filter works fine.
2000 GNC 5N\
2001 GNC 9N \ 40+ class
2004 GNC 9N /
2014 rock crusher "GO tortoise GO!"
2016 Byrd Rooster
Father of the "11" time National champion,and worlds fastest woman ATV racer
A few fast LT80's
250R~300cc's
300ex
350 Rancher
Kymco Mongoose
Survivor of the 12 Hours of ATV America 04 and 05