[asitis58]

I have a 2002 1800 with 63,000 showing. It runs great. I bought it about 3 months ago and it was getting about 44 mpg then. I noticed about 3 weeks ago that the mpg was dropping to about 36/38 mpg. It has being riden under about the same conditions as when it was getting 44 mpg. Gas, load and speed was all about the same. Checked the air filter out and it looked to be the original (nasty). Changed the filter and mpg stayed about the same ole 36/38 mpg area. I have been using about 2 oz. of marval mystery oil about every 3rd or 4th tank. Any ideas guys or is this what the bike is going to do with the milage.

 

[Foodman]

How much alcohol is your state putting in your gas now..
Here CA when that went from 5% to 10% my mpg was about 40/42 and now it's 38/39, 40 going down hill

 

[asitis58]

How much alcohol is your state putting in your gas now..
Here CA when that went from 5% to 10% my mpg was about 40/42 and now it's 38/39, 40 going down hill

10 % right now. Probably go up again one day. I did try some 89% marine fuel. No ethanol so they say. No change

 

[jackjohn]

Sounds about right for either of my 1800's. I can get 42 - 44 only on a road trip with the cruise locked at 65.

 

[Hanko]

One up running around town I get between 34-38. 1 Up riding on the highway at 55-60 I get 42-44. Using 10% ethanol. 2-3 mpg better with pure gas

2004 GL1800A

 

[DaveO430]

Check the air pressure in your tires.

 

[RKB53]

They may mix the fuel differently for a winter and also have a summer mix. I know up here in Conn. starting in November until April they use an oxygenated fuel for easier starting in colder temps. but this does lower the fuel mileage . Check what is written on the fuel pump next time you get fuel.

 

[Foodman]

They do the same thing here and when they the mileage goes to hell