does it take longer to start either hot or cold? Spinning the engine for longer time that it used to take?

My 08 was taking about twice as long to start and mileage dropped. I found a leaking in tank fuel hose. The one that goes from the pump to the filter. Replaced it and now it instantly starts and mileage went back up. Why a fuel leak, in the tank, would cause poor mileage is beyond me.

 

Jack the bike off the ground and spin the wheels. Check for dragging brakes.

 

The tank has a 4.7 gal capacity, at regular Highway speeds it will average about 40 to 43 miles t a gallon, 43 x 4.7 = 202.1 miles.

 

jdvorchak, it fires up instantly!

 

Glad to hear that. I wanted to cover all the bases


FYI I check my mileage at every fill up using the miles driven divided by gallons used. My Dyna pretty much stays in town and I get from 33 to 35 MPG. Sometimes when I combine a little, maybe 20 mile run down the interstate a couple of times, I'll see 38 MPG when combined with the in town riding.

But in my opinion the only way to calculate mileage is miles/gallons. Miles per tank means little to me. I usually fill up after 120 miles and use 3.5 to 3.8 gallons but my gauge says empty or close to it and the low fuel light is on.

 

Oh I stopped "trusting" the computer a long time ago! I go with amount of gas put in a topped tank always. This is why I know that there is something wrong with the bike in 4 years of use, only owner this is the first time this issue has shown up. I'm taking her to the Dealership this on Friday so they can run the diagnostics and see what's up. I'll let you guys know! Thanks for all your replies.

 

Are you sure you are putting in the same type of fuel? Reason I ask is if you are using that ethanol crap you're mileage will go to crap as well.

 

Ditch the Screaming Eagle plugs. Run just the regular Harley plug or NGK's. I've heard from several people that they fork out the money for the Screaming Eagle plugs and they have issues after installing them either poor mileage or just run terrible in general afterwards.

 

I just stop when we need it and ride on,
With a few bikes you take the same gas normally.
I seldom go by mpg mostly mph.
I usually use less then the heavy dogs.

Check your install,
Check your intake bolts.
Check your plugs,

 

Late to the thread but exact same issue here. 2016 RGS was running 300 miles per tank and about 48 mpg calculated at fill ups. Ran that way for a year. The change came after my 12,500 service. Suddenly dropped from nearly 300 miles per tank to no more than 200 about three weeks ago. 103 engine entirely stock, all services performed by dealer, alterations or work on it myself. I rode a SaddleSore from CO to TX and back this month and it was consistently getting 33-35 mpg the whole way--which the dealer service guys say is normal. No codes, no noticeable difference in performance. Tried a dozen different gas stations, speeds, altitudes, weights, new oil, even new tires--no change. IMHO it has to be the 02 sensor. Everything else I can think of seems like it would be a more gradual change. I am going to get the sensor replaced and see if it changes. I miss that huge range.