Every year I see my MPG drop about 10% in the Fall and early Spring when temps are in the 40'- 50's F. It looks like you have a 10% drop too.
2009 Wee Strom ABS (current)
1987 Harley FXR Low Rider Sport (current - with 206K miles)
2009 Aprilia Mana 850, 2006 SV650, 1984 Yamaha Virago 1000 (all sold)
Silver Strom Club Member #11
Wee Farkles: Russell Day Long Seat, Madstad with Moose Adventure Shield +4'', SWMotech Centerstand, 1'' up & back bar risers, Givi XS308 Tankbag, Aprilia mirrors, Framesliders, Fenda Extenda, Elka Shock.