JUST GOT MY CBR 600 . Its a 2003 , it has alot of miles but so far runs great its got 66,600 , which is alot for a bike and I was worried but , my opinion as long as you keep your bike serviced and change the oil , valves , and all the other important components , your bike or vehicle should live a long happy reliable life , ... anyways my bike doesnt get to great of gas mileage , im thinkin I get like 17 which is horrible but then again im always on the throttle ,,,, always unless im stopped , theres no coasting on a cbr 600 revs alit and soon as u let off the gas your droppin 20 30 mph quick , the bikes very fat ive only gotten it up to 127 mph and I think I was only at 9thousand rpm in 6th gear , if I was in 5th at that rpm I prolly b doin 140 I live these bikes , ive always wanted one , I cant just go ride my dirtbike everyday at the track or dessert , so I got a stret bike nd what a good decision I made ,
Congrats on your "new" bike! Looking at the other CBR 600's registered at Fuelly, I'd say you should be getting at least double your current mileage, even considering your heavy throttle hand. You may want to look into new plugs, wires, and probably a carb rebuild. With a 600cc motor you're getting a lot less mileage than I am on my Harley with a 1450cc motor.
I'm gonna agree with Jay here. You should be hitting 30 mpg all day long, heavy throttle hand or not. I'm pretty sure you have fuel injection, so I'll not suggest the obvious carburetor-related likely suspects. Check to see if the previous owner installed a power commander or had the ecu reflashed. Also, look into rolling friction, such as bad bearings, dragging brakes, or chain issues. That bike shouldn't slow down so fast when you get off the throttle, especially in 6th gear. It should roll out a lot better than you describe.
At 60 in 6th, you should be able to let off and roll down to 45-50 in maybe 1/4 mile, or about 10-15 seconds on flat ground. Try it by getting to 60 and just letting off the throttle, then do it again by letting off the throttle and pulling in the clutch. There should be a difference, in gear with the clutch engaged, it should slow down more quickly, but it won't be dramatic. If the speed drops off as fast as you say with the clutch in, you have a rolling resistance problem. I'm gonna bet a mortgage payment you have a brake dragging.
Congratulation grn3n714 for you pike, it's so early for you to get the best MPG out of your bike get it 2 or 3 months till you used to your bike , 17 mpg it's way too much for 600CC you may change your. Fuel injection due to the the age of the bike, or you have brake drag you have to lube your front and back wheels . I have Honda 2014 CB500X which is less CC than your bike however I get about 80 MPG in regular fuel , I ride 50 miles every days ,40 highway and 20 city but I ride very conservative I pull the clutch and let it roll in downhill or approach a red lights .
I used to have a 2007 CBR600RR. I NEVER saw less than 38MPG, averaged 40-41, and peaked around 44. I had a long commute with some highway, but I was pretty heavy on the throttle. I saw 15K RPM at least 3 times every time I rode it.
I think you've got issues somewhere. Maybe it just needs a tuneup.