Fuel efficiency: Unexpected differences (comparing each half of a round trip)
Guys (and gals?),
I just returned from my dad's house. I found a decent use for the A Avg/mpg. I usually fuel up before I leave to his house (140 miles one way) and do my fuel mileage. But this time, I thought I would use the A Avg/mpg since I had just refueled shortly before this trip.
Let me preface by saying this is not a complaint thread. It's all good. Very satisfied will the mpg so far. Far better than the EPA numbers.
So, as a general rule, I tend to always get slightly better mpg going north (from Atlanta south-side to almost Chattanooga), than I do returning home. Not sure why, but that is definitely the trend, even though I generally always run the same speeds. And since buying my Honda Rebel, my "official rated" mpg speed rating is at 72 mph. Why? Because my Honda Rebel 250 will only top out at 72 mph on flat level ground. Speedo says 75, GPS says 72. And on the interstate I just hold the Rebel WAO. It doesn't have enough power to hurt itself. And it will get about 56 mpg at WOT. So, 72 is my "qualification speed" just out of respect to my Rebel.
So, when I went to go to my dad's house Friday evening, I manually reset A Avg/mpg before cranking to leave my driveway. I drove up there and when I parked in his driveway it read 44.0 mpg. Not bad. That's probably ~42 mpg. I didn't have to reset the A Avg/mpg when returning home Sunday afternoon, it did it itself automatically. It read 48.8 mpg once parked in my own driveway. That's ~46.5 mpg.
Excellent mpg. But what I don't get is the huge disparity. That's a 6.8 mpg difference. Both times doing 72 mph. And usually it's better going north by about 0.5 mpg. So, it is very strange. Maybe I had a slight tailwind on the way home. It didn't feel like it. And on the whole 125 miles of interstate cruising, coming south, I canceled the cruise twice (besides to take my final exit). 72 mph the whole way through Atlanta. I find it fun to try to wade my way through traffic and not have to cancel the cruise, or use my foot to speed up. One cancel was merging from 75 south onto I-285. There's a really sharp curve that wouldn't be the best idea to attempt it in the Mirage at 72 mph. The other was just a traffic related cancel.
Anyway - I wanted to see if you guys figured it must have been a wind direction issue as well. Or ... something else? I had maybe 35 miles on that tank before the trip, and rode around in his town a couple times running errands for him. Now I'm back home and the whole fuel gauge area is flashing at me. Will refuel at lunch and report back.
Last edited by MetroMPG; 12-18-2020 at 03:21 PM.
Reason: (added info to title)
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View my fuel log 2020 Mirage ES 1.2 manual: 42.4 mpg (US) ... 18.0 km/L ... 5.5 L/100 km ... 50.9 mpg (Imp)