Flitemdic

Coming from the "Great White North", I can tell you the same thing happens to cars in the winter. We were always told it was because the engine "works" harder to keep the operating temp in the optimal range- more load on the engine= less mileage. (or so we were told)

Let us know how the switch out for the back works or whatever else you try please. I have the EXACT same problem with Sportmax's on right now. Mine is somewhat tire pressure dependant- if I go to exact measurements every single ride more than just to work, (42psi), it is somewhat less, but still there. I tried some of the above suggestions, no better, I didn't figure the tires until recently- I've always used the Sportmax, and have changed other parts- rims, etc, but there isn't really much else I can switch out.