bike runs good, but mpg seems low
Advanced
Joined: Dec 2005
Posts: 53
Likes: 0
From: Hollywood, MD
My '96 EG has never got that kinda mileage either. It don't matter whether I'm blastin around home or cruisin' to Georgia I get mid 30s. It has 10.5 wiesco pistons, bigger valves, Ev-27 cam, D&D Fatcat, and a CV carb.
Last edited by totinthapeach; Oct 21, 2009 at 01:08 PM.
Thread Starter
|
Tourer
Joined: Apr 2007
Posts: 356
Likes: 3
From: VB, Virginia
running at its optimum will get best driveability, power and gas mileage for the combo you have. i have a stock evo with very mild bolt ons. if my bike should get 50 mpg than i want it to run at its optimum.
if 50mpg is not the norm then i'm happy the way it is.
if 50mpg is not the norm then i'm happy the way it is.
Intermediate
Joined: Nov 2007
Posts: 48
Likes: 2
I've gotten 50-55 mpg out of every tank of 89-93 octane fuel I've put through the bike in the last 10k+ miles.....and the engine has 105k miles with the last top end being something like 60k miles ago.
Last edited by Kramer Krazy; Oct 21, 2009 at 02:45 PM.
Seasoned HDF Member
Joined: Aug 2007
Posts: 8,202
Likes: 3,089
From: NW AR
Mid 30's here at 70-80. Lower at higher speeds, higher at lower speeds. With our "Barn Door" aerodynamics, we're doing good for that. Wind will really make a difference. I have got 40's, especially on slower 2 lane roads and I think I did a little better with the Screaming Eagle carb, a Keihin from about 1988, than with the S&S, but it sure runs better with the S&S. I'm thinking about going EFI with a wide band and Megasquirt, but it does run quite well right now.
The Sportster gets about 50 right now. I could probably tune that a bit more, but it's running well, so don't f with it. With the original carb in the mountains, 55 MPH speed limit, before the windshield and with Dr. Linda new to the bike and not grabbing a handfull, we saw 90+ regularly and 100 a couple times. Of course, it was so lean that it was dangerous to pull out in traffic.
The Sportster gets about 50 right now. I could probably tune that a bit more, but it's running well, so don't f with it. With the original carb in the mountains, 55 MPH speed limit, before the windshield and with Dr. Linda new to the bike and not grabbing a handfull, we saw 90+ regularly and 100 a couple times. Of course, it was so lean that it was dangerous to pull out in traffic.
Elite HDF Member
Joined: Sep 2007
Posts: 4,468
Likes: 12
From: Bluffton, South Carolina
What you are getting isn't bad. However you might squeeze a few more out of it by undoing some of the "jet kit" modifacations. First check and see if they drilled out the slide, then check out the spring. A lighter spring and a modified slide allow them to rise sooner. This raises the already smaller needle and allows more fuel to flow in most RPM ranges. This is great if you ride it like you stole it, but if you are doing that you usually aren't worried about mileage. Hope this helps.
Intermediate
Joined: Aug 2009
Posts: 42
Likes: 0
From: AZ
40-ish is pretty good for a bagger (heavy) with a batwing fairing (wind drag). Most of the guys claiming 50 are exgaggerating, or riding a lighter bike. I recall a friend of mine claiming mid 30's on his 1996 EFI Road King, when it was new. I would agree with the others that tuning for every last MPG is a bad idea on an air cooled motor, the extra fuel keeps em cool.
FWIW, My FXD was pulling down mid 40's, up to 50 highway only, before I bumped the compression, running a bit on the lean side according to the plugs, but w/o any dead spots or rough areas throughout the RPM range.
After I bumped the compression to 10.5:1, the engine wanted to be fattened up everywhere, now it reads perfect on the plugs, runs like a raped ape, and knocks down mid 30's, perhaps pushing 40 highway only, which isn't very often.
My bike has stock unported heads, an EV-51, Mikuni 42, Supertrapp 2-1, Forcewinder A/C, Dyna 2Ki, amongst other things. And has been stripped of any unneeded weight. 24/48 Chain conversion.
I'll update after I drop in the close ratio 6-speed and regear to 22/51. Which will be any day now.
FWIW, My FXD was pulling down mid 40's, up to 50 highway only, before I bumped the compression, running a bit on the lean side according to the plugs, but w/o any dead spots or rough areas throughout the RPM range.
After I bumped the compression to 10.5:1, the engine wanted to be fattened up everywhere, now it reads perfect on the plugs, runs like a raped ape, and knocks down mid 30's, perhaps pushing 40 highway only, which isn't very often.
My bike has stock unported heads, an EV-51, Mikuni 42, Supertrapp 2-1, Forcewinder A/C, Dyna 2Ki, amongst other things. And has been stripped of any unneeded weight. 24/48 Chain conversion.
I'll update after I drop in the close ratio 6-speed and regear to 22/51. Which will be any day now.
Road Captain
Joined: Jun 2008
Posts: 640
Likes: 13
From: Hickory, NC area
90 FLHTCU with basani 2:1 exhaust, a hypercharger air cleaner, and a 180 main jet, 45 low jet (I think), and I get 42 almost all the time. When I was running at 80 across texas it dropped to about 38 once and once in the steep hills it dropped, but other than that it stays right around 42 for my normal riding conditions.
Road Captain
Joined: Apr 2005
Posts: 535
Likes: 14
From: Highspire Pa
Our 80" got about 40 mpg and the 113" gets about 35 mpg. I don't mind spending more money for gasoline but would feel better knowing I could go further without stopping for gasoline. We always use cash to buy gasoline. I hate stopping for gas at any gas station that requires you to pre-pay, and the number of gas stations in our area that allow you to pay after you fill up is getting smaller - so when we get about 120 miles on the tankful of gas we start looking for a station that does not require us to pre-pay. In our area, most Turkey Hill stores will turn on the pumps for a motorcycle without pre-paying.
joe
joe
HD Forum Stories
The Best of Harley-Davidson for Lifelong Riders
Harley-Davidson Fat Boy Becomes a Dark, Decepticon-Inspired Custom
Verdad Gallardo
6 Weirdest Harley-Davidsons Ever Sold to the Public
Verdad Gallardo
7 Times Harley-Davidson Chucked Tradition Out the Window
Verdad Gallardo
7 Surprising Harley-Davidson Products that Are Not Motorcycles
Verdad Gallardo
8 Best Harley-Davidson Motorcycles Ever
Pouria Savadkouei
10 Worst Harley-Davidson Motorcycles Ever
Pouria Savadkouei
Killer Custom's Jail Break Is The Breakout That Refused to Blend In
Verdad Gallardo
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Verdad Gallardo
Harley-Davidson Reveals Super Cool Cafe Racer Concept
Verdad Gallardo
HDF Community Team
Joined: Dec 2005
Posts: 5,430
Likes: 2,632
From: NC USA
Well, I'm one of those who bragged about 50 mpg at moderate speeds... recently pulled the heads and the cylinders were white-streaked from heat. And even with the setup I was running, it was down to 33 mpg at high speeds (80mph) in a cross wind and mid 40's with any cross wind at moderate speeds. So I had to come off the setup I was running...
Cross wind wind or even a breeze will make a tremendous difference, not to mention speed and your throttle habits and how many times it's started cold on a tank of fuel. And, how you check the mileage will make a difference too. If low 40's is the best you get under any condition driving like an old lady (as I do most times), then you might improve on that a bit, but you're real close. Idle screw adjustment will make a good bit of difference as will the taper of your needle. There are about 40 diferent needles that will fit that carb I just found out recently...
And remember, all these "modifications" you read about are for performance and seldom equate to economy. However, if it's too lean mileage can suffer as easily as being too rich. It's the Goldilocks and the 3 bears story - needs to be "just right."
Cross wind wind or even a breeze will make a tremendous difference, not to mention speed and your throttle habits and how many times it's started cold on a tank of fuel. And, how you check the mileage will make a difference too. If low 40's is the best you get under any condition driving like an old lady (as I do most times), then you might improve on that a bit, but you're real close. Idle screw adjustment will make a good bit of difference as will the taper of your needle. There are about 40 diferent needles that will fit that carb I just found out recently...
And remember, all these "modifications" you read about are for performance and seldom equate to economy. However, if it's too lean mileage can suffer as easily as being too rich. It's the Goldilocks and the 3 bears story - needs to be "just right."