Hi Bikers, I have pre owned Yamaha FZ of 2010 model, when i bought this bike it was giving me a mileage of 28-30 in highways.After i serviced ( oil change + oil Filter change + Airfilter change + carbarator diaphragme changed. Chain sprocket and tyres are new.). Now i get 32 mileage which is not a good mileage as compared to other FZ and lacks in power. Local mechanics and few bike owners suggest me to check the carbon deposits in engine head as it has ran for around 40k. If so decarbonize and do the valve settings etc for better performance and efficiency. I had driven my friends FZ (2009 model) which was giving 42-44 mileage . I expect at least 40 mileage from my bike.So guys pls let me know what needs to be done for getting good mileage?. Pls help. Thank you