My bike doesn't go over 115-120km. I used to get 135-140km. All seems okay but in 5th and 6th gear, RPM doesn't go over 9000. If I pull the clutch, then it goes over 9000. My rpm doesn't want to go over 9000 from 5th gear, and speed increases very slightly. And my throttle also reacts slightly late. Bike performance decreases rapidly when riding with pillion.

Can someone please tell me what is the problem with my bike?

BTW my weight increased from 65 kg to 80kg. I always used Mobil 1(10w40) engine oil. And I maintained tyre pressure 35-45.

Bro I too have same problem in my bike r15. Did the problem get solved. What was the issue bro!