Fuel Efficiency Concerns 1997 FLHRI
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Joined: Jan 2013
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From: Austin, TX
Fuel Efficiency Concerns 1997 FLHRI
Some of you may have read my thread about bike not starting.
After I solve this problem I need to look into why my bike gets VERY poor fuel economy.
On the 6 tanks I have been through since I have owned the bike have averaged 22.5 mpg. That is absolutely awful. I am wondering what could cause this as I know I should be doing a bit better.
Few facts.
Has a CAM. (no idea on details was done by PO) Has Thunderheader Exhaust, Aftermarket Air Cleaner (no idea on model/type as isn't apparent), and is the MM EFI model.
Any thoughts on what I should look for would be great. I know I should be doing far better than this on my bike. My truck gets about this on the highway so that concerns me a bit.
After I solve this problem I need to look into why my bike gets VERY poor fuel economy.
On the 6 tanks I have been through since I have owned the bike have averaged 22.5 mpg. That is absolutely awful. I am wondering what could cause this as I know I should be doing a bit better.
Few facts.
Has a CAM. (no idea on details was done by PO) Has Thunderheader Exhaust, Aftermarket Air Cleaner (no idea on model/type as isn't apparent), and is the MM EFI model.
Any thoughts on what I should look for would be great. I know I should be doing far better than this on my bike. My truck gets about this on the highway so that concerns me a bit.
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Joined: Jan 2013
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From: Austin, TX
Plenty of places in Austin to dyno the bike. Is that where I should start? Or are there other things i should look at first that might be wrong with it? Or are you just saying it might be extremely poorly tuned?
Road Master
Joined: Nov 2012
Posts: 794
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From: Alvin TX
At just 22.5 I would say bad tune, my 94 evo softail get easy 50 mpg but its a lighter bike My brother has A 98 E glide ultra rides two up all the time & gets about 40 he has the mm efi with a pc non stock air cleaner & rush pipes with V&H true dules & ev 27 cam he was down to about 29 mpg then I told him to get it dynoed & now up to 40 mpg they ride all over the country & it stays right at 40 so a good dyno should help unless you rn wot all the time & take off like a rabbit 
Stellar HDF Member
Joined: Feb 2007
Posts: 2,558
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From: Russellville, Arkansas
I would either find a Scanalyzer or have a dealer plug your bike into their computer. This will tell you what the current ECM flash is. It is possible you have the wrong flash for the build. Then again, it may have never been reflashed.
On my 1998 Ultra, I have the EV27, SE air filter, red fuel injectors, and slipon exhaust. It also has the stage 2 download for the ECM. It averages 45-50 mpg and low as 37 mpg on the highway traveling 80+ mph.
I had a 1997 Electra Glide Cop bike for about a year. It had the same setup as my 1998 does and got horrible fuel mileage. The previous owner reflashed the ECM to stage III which was way too much for the build. I found a stage 2 cartridge on Ebay and reflashed...fuel mileage instantly went up.
Anyways, easy thing to check....
On my 1998 Ultra, I have the EV27, SE air filter, red fuel injectors, and slipon exhaust. It also has the stage 2 download for the ECM. It averages 45-50 mpg and low as 37 mpg on the highway traveling 80+ mph.
I had a 1997 Electra Glide Cop bike for about a year. It had the same setup as my 1998 does and got horrible fuel mileage. The previous owner reflashed the ECM to stage III which was way too much for the build. I found a stage 2 cartridge on Ebay and reflashed...fuel mileage instantly went up.
Anyways, easy thing to check....
Seasoned HDF Member
Joined: Feb 2007
Posts: 6,066
Likes: 1,121
From:
Review the two fuel lines that attach to the tank at the bottom.
The fuel lines leak at the swivel (Almost like a sweat at first).
Any chance the bike smells a little like gas when parked?
Do you notice that your left pant leg smells a little like gasoline?
Any marks on primary of gasoline drops?
If replacement is required the two hoses are very expensive from Harley but Goodridge sells the HDFL005 hoses.
Google: Goodridge HDFL005.
Check internet pricing and price shop because the Goodridge hoses run $145 to $200 total for the same exact hoses...both included included in package at that price.
Harley hose is at least double the cost.
Also: with the set-up you describe you should be running lean/hot unless something was done to add fuel. Check under the side covers and also under the seat for a piggy back fuel adder box like a power commander, V & H, revtech DFO etc. maybe someone dialed the numbers high and the machine is just dumping fuel.
Finally, on a 1998 MM road king (pipes/aircleaner/power commander) the worst mileage i can remember was about 28-30mpg and the external lines had a very slight leak, it was at high speeds and on the new ethanol fuel.
The fuel lines leak at the swivel (Almost like a sweat at first).
Any chance the bike smells a little like gas when parked?
Do you notice that your left pant leg smells a little like gasoline?
Any marks on primary of gasoline drops?
If replacement is required the two hoses are very expensive from Harley but Goodridge sells the HDFL005 hoses.
Google: Goodridge HDFL005.
Check internet pricing and price shop because the Goodridge hoses run $145 to $200 total for the same exact hoses...both included included in package at that price.
Harley hose is at least double the cost.
Also: with the set-up you describe you should be running lean/hot unless something was done to add fuel. Check under the side covers and also under the seat for a piggy back fuel adder box like a power commander, V & H, revtech DFO etc. maybe someone dialed the numbers high and the machine is just dumping fuel.
Finally, on a 1998 MM road king (pipes/aircleaner/power commander) the worst mileage i can remember was about 28-30mpg and the external lines had a very slight leak, it was at high speeds and on the new ethanol fuel.
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Joined: Jan 2013
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From: Austin, TX
IM
No fuel smell anywhere.
No marks of gas drops.
Sounds like I should just take it to my local guy to have him check what it is flashed for. No reason I should be doing so poorly with fuel efficiency.
No fuel smell anywhere.
No marks of gas drops.
Sounds like I should just take it to my local guy to have him check what it is flashed for. No reason I should be doing so poorly with fuel efficiency.
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Elite HDF Member
Joined: Sep 2007
Posts: 4,468
Likes: 12
From: Bluffton, South Carolina
It may or may not have the original ECM flashed. It may have an aftermarket tuner of some type installed. The tune would have to be way off for it to get that mileage. Perhaps a sensor is bad making it run rich??? How do the plugs look???
John
John
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Joined: Jan 2013
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From: Austin, TX
Plugs look great actually. Little white on the tips. Little dark on the threads but not burnt. No melted tips. All indications appear that it is a normally used plug. I am going to replace them just so I know where the maintenance is at on them. But they would be fine being left in.