Question about Running "Lean"
Cruiser
Joined: Dec 2010
Posts: 105
Likes: 3
From: Western Nebraska
Question about Running "Lean"
I am not a mechanic, I can do maintenance such as change fluids, filters, plugs, etc.
My question for someone in the know is this, why does an engine run "hot" when it is running lean? I don't have a real reason to ponder this because right now my 2004 Ultra is fully stock so it probably doesn't matter to me. I just want to know.
My question for someone in the know is this, why does an engine run "hot" when it is running lean? I don't have a real reason to ponder this because right now my 2004 Ultra is fully stock so it probably doesn't matter to me. I just want to know.
Intermediate
Joined: Apr 2009
Posts: 38
Likes: 0
From: Georgetown, TX
Check out this site for a good explanation on engine heat: http://www.nightrider.com/parts/hd2007hd_heat_00.htm. The XIED really works on cooling down the engine, and it's not too expensive...
Banned
Joined: Nov 2009
Posts: 2,119
Likes: 651
From: null
I am not a mechanic, I can do maintenance such as change fluids, filters, plugs, etc.
My question for someone in the know is this, why does an engine run "hot" when it is running lean? I don't have a real reason to ponder this because right now my 2004 Ultra is fully stock so it probably doesn't matter to me. I just want to know.
My question for someone in the know is this, why does an engine run "hot" when it is running lean? I don't have a real reason to ponder this because right now my 2004 Ultra is fully stock so it probably doesn't matter to me. I just want to know.
Extreme HDF Member
Joined: Apr 2006
Posts: 10,449
Likes: 46
From: Roswell, GA
Your stock '04 doesn't have the heat issue that is so common now. HD started leaning out fuel in '07 for EPA compliance thereby creating an aftermarket industry to address the heat created by leaner fuel delivery.
Carl
Carl
Elite HDF Member
Joined: Apr 2008
Posts: 3,900
Likes: 4
From: way down upon the Suwannee River
#2 on the Nightrider IEDs I've had mine on for 70,000 miles now , no problems and runs a lot cooler.
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Seasoned HDF Member
Joined: Aug 2009
Posts: 9,228
Likes: 3,238
From: west Michigan
If your '04 is stock, it's running too lean; maybe not enough to damage the engine but enough to affect performance. You can keep the stock mufflers and still get significant gains from a low restriction air cleaner and fuel minder like the Dyno Jet Power Commander III or V. I know because that's what I did for my '04 FLHRI with a PC V and map from Fuel Moto.
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