To all,

Makes sense, I haven't checked it, but for those that have, do you get significantly worse MPG with top case in place than without?  I'm 5'9", assume it would affect MPG.

I remember clearly getting 44/45MPG, and I'm running my top case almost 100% of the time, and my AVG is now 40+/-.  Assume it's the case.  May ride to work without it today and test.

Barry

I'd be very surprised if the effect is much at all.  Your body is blocking most of it.  I hear the same thing about taller windshields and I don't believe that either.  I ride with a guy with an identical bike as mine except I have the previous (08-09) windshield on mine and he has the newer tall windshield on his.  We get about the same mileage riding together.  Look at the profile from the front of the bike and the windshield or the trunk make up very little of the "frontal area" of the vehicle with the rider on the bike.

My mileage goes up with a shorter shield, so I don't doubt it.
How smooth the air is behind you counts as much as the frontal area.

I can't say from experience as probably less than 1000 of my 56000 miles has been without a topcase. I also beleive it is difficult to predict the aerodynamic effect. Depending on the riders size and shape a topcase could concieveably clean up the air behind the bike.

I have noticed that there seems to be no decrease in MPG riding two-up vs solo.

I have noticed that there seems to be no decrease in MPG riding two-up vs solo.

+1 but only because my "cruise control" is sitting behind me punching me in the ribs if I am working my right wrist to hard.   

My behemoth E55 litre top box consistently yields 44/45 MPG in "ECO" mode.  I have no idea if it would be better without the box as its been on since I've been paying attention to mileage. 

Bitchin' tags, dUDE!

Anything that the air hits will affect your MPG. I have a Cee Bailey ultra tour domed, when I ride with it down and have my readout on AVERAGE MPG than I lower it I can see the AVERAGE MPG go up but not but 3 or 4 MPG, maybe 1/2 to 1. On my Gold Wings i have had in the past a bigger shield always got you lower miles but about 3 or 4. The top case would probably cause a slight decrease in your MPG also, ever notice pick-up trucks going down the road with their tail gate open, unrestricted air flow,

To all,

Makes sense, I haven't checked it, but for those that have, do you get significantly worse MPG with top case in place than without?  I'm 5'9", assume it would affect MPG.

I remember clearly getting 44/45MPG, and I'm running my top case almost 100% of the time, and my AVG is now 40+/-.  Assume it's the case.  May ride to work without it today and test.

Barry

Barry, have gained a few pounds and now tried to blame the bike?   

I have no drop in MPG with top case, but I do when I run with the side bags, so I run mostly with the top box.  I get the worse MPG when I have neither on, but then again, whadaya ya expect when on the track???  I commute 80 a day so MPG IS important to me, but when I'm out having fun not so much.  My best MPG is when SWMBO is on back, much smother inputs, speed limit 99.9% of the time.  Based on this, I would say the top box does not add to the decrease in MPG, rather, the side bags do.  Only 49400 miles, so my estimates may be off, but I have an overall average of 41 MPG for the life of the bike, the vast majority sans side bags, with the Shad 46 mounted.

My passenger never slows me down. In fact she gets impatient when the pace is too slow on a group ride.

My passenger never slows me down. In fact she gets impatient when the pace is too slow on a group ride.

Does she have a good-looking single sister? 

My passenger never slows me down. In fact she gets impatient when the pace is too slow on a group ride.

+1, mine neither, Not even on the TRACK, gotta' love those "awesome gals' 
 

Bitchin' tags, dUDE!

Thanks, Paula has GA tags on that bike, we wouldn't want anyone to know that!

On my 2010 I keep it in ECO mode. Stock windshield and a sears top box and I am sitting at 43 mpg with 93 octane gas.
With my old 2008 I had the same case on it and Cee Baileys Euro shield and went from 42 mpg down to 37 mpg.
So they do play a big role in mpg.
 I love my 2010 Eco-mode and newer windshield.

MPG?
 
I can't seem to ever get my average MPG on the display above 32.1...
 
Should I change music when riding??

 So... full disclosure.

I noticed the drop last fall.  Assumed it was our crappy Ethanol gas. 

At the same time I got a Cee Bailey's Euro Cut (IIRC).  Taller, wider.  Assume that or the Ethanol was the culprit.  This spring, I took the CBEC off the bike, and I'm running an OEM screen cut down 4".  I believe that *may* also be affecting the MPG average.

Just had the 30K tuneup done on the bike.  On the way to work, reset the MPG AVG and on the highway saw a high of 47 MPG AVG - not instant/realtime, AVG.  My AVG not resetting for a week or so hovers at 40, and I used to average 43-44.

I'm not discounting the combo of the shield(s) and the top case.  I ride VERY far forward, and I'm not tall.  I believe in my configuration the top case may be really dirtying up the wind behind me, and thus destroying my MPG.  I'll ride without it and see.

Barry

My mileage goes up with a shorter shield, so I don't doubt it.

+1

Not that I"m concerned with MPG but....currently getting a displayed 45+ fully loaded with trunk. No flies, slip on and PC3, cb mini-euro shield.

MPG?
 
I can't seem to ever get my average MPG on the display above 32.1...
 
Should I change music when riding??

Now there's a thought.  I ride faster/slower depending on what the voices in my head tell me...