Should I go up 2 or 3 on the rear?

[lankeeyankee]

I am +3 on an 09
Gas mileage went from 43 to 39 on my daily interstate commute to work.
1st gear is still able to run over the legal speed limit
Takes away 14MPH Top speed is 172 on GPS (restricted)
I like the gear change cause alot of my riding is around 75MPH and it gets past that buzzing vibration in the handlebars.
Down side is you will eat rear tires faster if your hard on the throttle.

If you don't ride hard and scared of the wheel lifting with just power thru gears 1-2-3 leave it with the stock gearing.

 

[EarlyBird]

With my +3 rear sprocket (46) and the 190/55 tire. I average 39-41 mpg on my daily rides to and from work. This includes city and highway. On highway runs 44-46 mpg seems to be normal. All city in the 35-37 mpg range. I have mine unrestricted and it has gone 180 plus with this gearing. The pics below are of the speedohealer showing the highest speed attained. I was running out of road. Still more in it. I ran it 2 different times that day. The higher mpg being the second run. The speedohealer was setup with a GPS and its with in 1+/- a MPH at 45/55/65/75/90 mph.