OK. I want to know why we don't get better MPG. For that matter, why all motorcycles don't get better MPG.
Take for example a Toyoto Yaris. Curb weight 2290lbs, a 1.5 liter engine, and 29/35MPG.
Our Savages are under 400 pounds wet, with a 0.65 liter engine, and we get somewhere in the neighborhood of 55-60mpg stock. WHY?!

I realize that factory estimates of MPG don't factor in certain variables, and nowhere is that more apparent than on motorcycles; weight of the rider, flex of the right wrist, mods, etc., but a stock factory to stock factory comparrison still leaves us on the short end. I mean, the Yaris weighs six times the Savage, but only gets half the mileage. Put the opposite, the Savage weighs one sixth the Yaris but only gets double the mileage. Shouldn't it be more????

I'm no engineer, so I appeal to you who know far more than I to help me understand this. (Especially when I can't get my wrist to behave and get only 45mpg. )
Thanks

I know what you mean about poor mileage on the Savage. I have a 120HP,1639 cc chopper that is not one bit aerodynamic, with a 45mm carb, weighs 550lbs, and it gets 50-55 MPG. To me that makes no sense what so ever.   Hutch

  The s40 would get a lot better if it weren't geared so low,turns more rpms then it needs to.

All great answers, and I thank you.
mornhm,
I had not considered the aerodynamic differences to be a negative factor for the motorcycle. Your explanation makes perfect sense.

Hutch,
Hang on to that chopper, man. That's great MPG! Especially for that size engine.

skrapiron,
So it kinda makes it an unfair apples to oranges comparrison, doesn't it? I hadn't thought of weather beyond a headwind. It would, and does, wreak havoc with a carb. You're also right about changing anything on the bike, it wouldn't be a Savage anymore, and I couldn't love it like I do.

bill67,
See, that's the kind of thing I just never think of. I listened to my motor on the way home, became really aware of when I was changing gears, the subtle differences in RPM. It does tend to run more like a hummingbird, doesn't it? That would chew up gas!

WOW, thanks guys. It makes sense. Motorbikes could be changed to offer up more MPG, but they'd run the risk of not being motorbikes anymore, wouldn't they?

If I remember correctly, resistance to air goes up by the square of the velocity of the moving object....IF I remember correctly.  So you can see what the effects of aerodynamics has on MPG.

I think the sprocket ratio is the biggest factors because some folks have gotten much better at a 45-50 mph pace, I think I saw a claim of 70 here once.  I wwould consider the chain conversion, but I do like the belt, an extra tooth up front and maybe 2 less out back would sure change things.  A swoopy fairing would help problem #2, wind resistance.  Fuel injection would only give a marginal mileage improvement, but would be far better for driveability. IMO.

I too have wondered why the Savage's MPG is so meager when compared to much heavier bikes.

Skrapiron's response about the lack of fuel injected/computer is right on the money.  The antiquated carburetion is the main culprit.

Considering the Savage's low cost its no surpise its so bare bones.  You pay for what you get.

I ain't complaining though, I ride my 2007 Savage to work daily and average 54MPG.

I burn only 2 gallons of gas a week, cost is $8 weekly, gotta love it.  

With my original '03 Savage, I got approx. 68-70mpg on a couple of Rides that were a steady hour to hour-and-a-half at 40-50mph ... haven't checked to see what my S40 is doing (yet) ...