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42mpg...why???

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Old Jun 23, 2007 | 03:51 PM
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Silvia
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Default 42mpg...why???

Why am I consistantly getting 42mpg. The carb is set with 175/46 (still farting) and I am out 3 turns on the mixture. I drive 50/50 highway/city. I don't really even beat the damn thing. Tires are at 32/38lbs.

2006 883 - SE AC, V&H Straight shots

WTF???
 
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Old Jun 23, 2007 | 04:12 PM
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cHarley
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Default RE: 42mpg...why???

Assuming you don't ride your bike hard like you say, 42 MPG is low. How many miles are on the bike? Is it still under warranty? Who decided the 170/46 jets were right for your bike? Have you had it on a dyno or are you tuning it by guess work? While 3 turns out may work on a few bikes,by far 2 - 2.5 turns out is typical. Given the continued farts with the mix screw out 3 turns and a 46 low jet something is not right.

Even though I do my own wrenching there are times when you may have to break down and take it to the dealer or indy where they have diagnostic equipment us shade tree mechanics can't afford, like a dyno, to find out what's really going on. Have you checked for vacuum leaks? Your carb may be set to rich trying to compensate for a vacuum leak.
 
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Old Jun 23, 2007 | 05:54 PM
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Default RE: 42mpg...why???

What octane gas are you running .Mine runs worse on lower than 90.Also what brand are you using .My mpg drops way down with Caseys gas on hi way from 56 to 45
 
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Old Jun 23, 2007 | 06:13 PM
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ZD
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Default RE: 42mpg...why???

What do the plugs look like? They'll tell the story on your combustion.
 
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Old Jun 23, 2007 | 09:40 PM
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Default RE: 42mpg...why???

looks to me like your running to rich .
 
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Old Jun 23, 2007 | 10:52 PM
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Default RE: 42mpg...why???

I did my jets based om what the local dealer told me. He said to cure farts go 45 slow and 3 turns. Well that did not cure anything so I went with the 46...of course still the same.

THe plugs are black on the outside and tan on the electrode. Is that normal? I know we have to run this crappy reformulated gas here in the Milwaukee area which accounts foraloss of3-4 mpg but it still seems low. (cleaner fuel, but you burn more...I don't see the point)

The engine has just under 2000 miles on it. I have heard these engines get better mileage with age. Is this true?

Is there anything else I should check to at least cure the farts? I can go back to a 4 low and 2.5 turns.
 
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Old Jun 23, 2007 | 10:57 PM
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Default RE: 42mpg...why???

Hell. I'm happy if I get over 35.
 
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Old Jun 23, 2007 | 11:00 PM
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ZD
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Default RE: 42mpg...why???

ORIGINAL: Silvia

I did my jets based om what the local dealer told me. He said to cure farts go 45 slow and 3 turns. Well that did not cure anything so I went with the 46...of course still the same.

THe plugs are black on teh outside and tan on the electrode. Is that normal. I know we have to run this crappy reformulated gas here in the Milwaukee are which accounts for typically 3-4 mpg but it still seems low.

The engine has just under 2000 miles on it. I have heard these engines get better mileage with age. Is this true.

Is there anything else I should check to at least cure the farts? I can go back to a 4 low and 2.5 turns???
If the plugs are black on the outside, you're a littletoo rich. If you mentioned fuel octane, I missed it. I would recommend the highest possible octane rating, a fresh air filter element and a nice long ride... then recheck the plugs. If they're still black around the outer edge, then you need to lean it out a wee bit.

Also check your intake manifold connections. If you're pulling any air in after the carb, it'll give you the same symptoms. You might be able to'cure' the symptoms of a small intake leak with a rich jet setting, and it would likelygive you exactly the symptoms you have.
 
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Old Jun 23, 2007 | 11:07 PM
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itileman
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Default RE: 42mpg...why???

By "reformulated" do you mean Ethenol or RFG (Reformulated/Oxygenated)? HD recommends the RFG and a 10% blend of Ethanol with gas is OK too. I run straight 91 Octane in my 883 with no problems and get in the mid to upper 50mpg. A lot less against the wind. Runs great this way and I don't buy off-brand gas for it.
I'm about to go to SE slip-ons, K&N replacement filter and mess with the jets, starting with the slow only on the advice of a guy who owns a rental fleet of HD's. Ride at 3,000 - 6,500 ft most of the time.
Any advice or comments on this would be appreciated as this is my first Harley.
 
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Old Jun 24, 2007 | 07:19 PM
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Default RE: 42mpg...why???

I think I have her dialed. It took all damn day, but 175/45 1.25 turns out. It is like a totally differnt bike. It hasa lot more get up and go now. I guess it was really rich and bogged down before. Hopefully the gas mileage will be better now. Guess I have about 120 mile until I find out.
 
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