I used to ride my FZ 40 kms daily & i was getting a mileage of 55 kmpl . But recently my mechanic do some changes in the clutch setting , he loose the clutch , because i complained him about tightness in riding in top gear feels like im riding in 3rd gear . So he loose the clutch , but after that my bike mileage reduced to 40. Can any one tell me why this happened