Fuel mileage and volts

Hi guys, 2 questions...
1) Since the cooler weather moved in (30's for the low and 50's for the high) I have been getting diminishing fuel mileage, not bad. was 39mpg...is 35mpg. Will the cold air cause this or is it a carb problem.

2) volts at idle (1100 rpm) are only 12ish, when cruising they are around 14v, is that normal?

Thanks Joe

 

Sounds normal to me

 

1. cold engine
2. normal

 

Shouldn't cooler air lean the fuel mixture?

 

My '97 does the same thing. I ride year round, lately about 25F going into work about 50F coming home. I've blocked off the oil cooler and partially blocked off the radiator to get the temp up a bit-runs much better.

 

Winter blend gas has a lot to do with lower gas mileage also.

 

oxygenated gas for winter = crappy mileage.