So I didn't think it was such a big until one of my friends told me that my chugging around 8k rpms on 4th gear and up is a bad :technical:, so anyone has any clue what causes this?
What do you mean by 'chugging'? Similar to the 'lug' that you get at low rpm's? Or is it just a noise that it makes?
Sounds like a lean condition. Might be an air leak somewhere. Check the carb boots.
could be a vacuum leak between the carbs and airbox too. had this happen on an older yamaha maxim and it would get to about 7500rpm and stop like a rev limitter.