2004 and beyond - better gas mileage?

I was reading a review of the 2009 gz250 and the author said that in 2004 Suzuki redesigned the combustion chamber that year, and so that model and the years since get better gas mileage than earlier model years. Can anyone verify that, and if so, what kind of difference are we talking about?

Keith

[Easy Rider]

I was reading a review of the 2009 gz250 and the author said that in 2004 Suzuki redesigned the combustion chamber that year, ......

Based on somebody else's search for a rear sprocket, it would appear that they may have added one tooth to the rear about that same time too. If that is true, a meaningful comparison might be difficult.

[Chris]

My 2000 GZ250 does great on mileage. I ride easier than most guys (my cars beat the EPA gas number!). My GZ usually gets 75mpg with my easy riding. Really easy riding (alone in the country) can get me over 80mpg. Interstate riding at 70mph gets 62mpg because I am so near (or at) full throttle.
Probably making an easy trip alone tomarrow for 200 miles so looking for 75+mpg.
I ride often with guys with 1000+cc bikes. Often I am in the front (I usually organize the rides) and my mileage goes down to 68-70mpg because I turn up the revs just a bit when with the big bikes. I can easily ride the speed limit so even with their huge engines our group simply rides the speed limit everywhere we go.

Chris, retired near Atlanta

[patrick_777]

Remember that the average ethanol content in gasoline has risen considerably in the past few years, so that will negatively affect mileage.