Proof you don't need a tuner
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Joined: Apr 2012
Posts: 50
Likes: 3
From: St. Augustine, Florida
Hello all. I would have totally expected the FI to compensate for pipes and maybe an AC. Although, I just bought a "48" at my dealership that was traded in with 500 miles on it. All they did was Vance and Hines slip on mufflers and heat shields. The bike runs like hell. Surges, misses while on a constant RPM (Cruise). WOT bike hauls great, but any kind of slower consistant speed and she sputters and just does not run right. I took the intake and throttle body off. Cleaned the injectors, made sure nothing settled in the tank(you never know). I polished out the intake and throttle body. That is where I am at now. I haven't tried it now and yes I realize i made the lean issue worse until I tune it. I wont run it until I get a tune in it. I tried a few different things before to get it to run smoother/richer. 93 oct. Mixed a little 110oct with it. Put a step colder plugs in it. Ran some sea foam through the tank. Still was running lousy before I took the intake off. I have a new AC and different Pipes on order along with which ever tuner I decide to get. So I don't know. Slip on pipes have seemed to be too much for the 1200's EFI system to compensate. Any thoughts? I am sure the bigger bikes have a better designed motor.
Road Captain
Joined: Dec 2005
Posts: 673
Likes: 30
From: Warrington England
Different Expierience
I really wish I had the same results as the original Poster,& a lot of others in the thread,I changed the Pipes on my 11'FXDF for a 2-1 system,& the bike runs really poor,lots of back fireing bad decel popping,feels relatively gutless,don't know why but my ecu has definately not adjusted to the new system,not making a point,just a very different result.
Road Captain
Joined: Jul 2009
Posts: 636
Likes: 1
every time i have the bike serviced it comes back running like ****,disconect the battery for at least one hour,let it sit,for some reason this seems to start the ball rolling,reconect take the bike to a open road run it up to about 5000 rpm in different gears then backing off and letting it back to about1500 rpm like you are brakeing in a new motor after that it will get better with time till they service it again. why this works I have no idea, but it sure helps mine.had it serviced and headed for my sons ran like **** unhooked the battery at his house for sum reason don"t remember why when I left his house and headed home was pissed ran the hell out of it started to straiten out. he live on a two lane in the country so I ran it up and down like stated to the city limits by the time I got home it was running decent.and two days later no popping and running good
Club Member
Joined: Jun 2007
Posts: 45,429
Likes: 2,898
From: Bedford UK
As usual when this subject is raised we get a lot of repeated folklore and misinformation. A stock bike has air/fuel ratios set to maintain EPA regulations. It will allow us to ride over the highest mountain pass, through the hottest desert and coldest winter and maintain those settings.
That built-in adaptability is what you are using up when changing things like mufflers and air filters. It is not there to allow us to change stuff. The days of backyard tuning are behind us. We need to get smart when modifying modern bikes and the only certain way of ensuring all is well is on a dyno.
That built-in adaptability is what you are using up when changing things like mufflers and air filters. It is not there to allow us to change stuff. The days of backyard tuning are behind us. We need to get smart when modifying modern bikes and the only certain way of ensuring all is well is on a dyno.
Tourer
Joined: Aug 2008
Posts: 381
Likes: 2
From: Florida
As usual when this subject is raised we get a lot of repeated folklore and misinformation. A stock bike has air/fuel ratios set to maintain EPA regulations. It will allow us to ride over the highest mountain pass, through the hottest desert and coldest winter and maintain those settings.
That built-in adaptability is what you are using up when changing things like mufflers and air filters. It is not there to allow us to change stuff. The days of backyard tuning are behind us. We need to get smart when modifying modern bikes and the only certain way of ensuring all is well is on a dyno.
That built-in adaptability is what you are using up when changing things like mufflers and air filters. It is not there to allow us to change stuff. The days of backyard tuning are behind us. We need to get smart when modifying modern bikes and the only certain way of ensuring all is well is on a dyno.
Tourer
Joined: May 2012
Posts: 262
Likes: 1
From: New Jersey
What does this even mean??? Did you install it yourself?? If it didnt connect right...thats on you...and please clue me in to how it "messed up your main wiring harness." Sound like you shouldnt be working on your bike...or shouldnt be taking it to be worked on where ever you did......
Seasoned HDF Member
Joined: Aug 2010
Posts: 5,173
Likes: 177
From: East Coast
I've said it before...I wish I kept the copies of HDs own tests putting A/Cs on and pipes with no tuner. No problems whatsoever.
Stage 2 A/C, full 2:1 pipe change, no cats, adjustable baffle 80% wide open. Runs GREAT. Plugs are consistently a light tan. No carbon build-up inside exhaust. No download. No tuner. No surging. Less heat (no cats). Some decel pop, which, if it were 100% missing, I'd tune it back in!
Stage 2 A/C, full 2:1 pipe change, no cats, adjustable baffle 80% wide open. Runs GREAT. Plugs are consistently a light tan. No carbon build-up inside exhaust. No download. No tuner. No surging. Less heat (no cats). Some decel pop, which, if it were 100% missing, I'd tune it back in!
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Road Captain
Joined: Jul 2011
Posts: 737
Likes: 8
From: Near Atlanta, GA
I ran my 2011 FXDWG with full V&H, heavy baffles & Stage 1 for about 1000 miles without doing a tuner / Dyno run, but could tell the bike was running really lean. I tried to go on the cheap with the XiED and while I initially thought it helped, that was short-lived. (Anyone want the thing for 1/2 price?). I took it off and let the ECU go through a couple tanks of gas to get sorted out again and just accepted the fact that until I put it on a Dyno and had it checked I wouldn't know what the motor was really doing.
Turns out it was running WAY lean...
On the baseline run (Red Line), AFR held at a very lean ~15.0 in the 2,400 – 3,500 RPM range that decayed to ~13.5 at 5,500 RPM and then ~13.0 at 6,200 RPM. After the tune & a few hours with the tech getting it dialed-in, it was a solid ~13.5 all the way across the board, +/-.1 (Blue Line)
Bear in mind, Harley's OEM spec is around 14.6, which is pretty darn lean & hot to begin with.
Horsepower & torque also improved, but it was the AFR that I wanted to get sorted out.
Red line = Baseline, Blue line = after the tune.
Your results may vary... I REALLY wanted the stock ECU to bridge the gap, I really did. And, for some perhaps it does.
Turns out it was running WAY lean...
On the baseline run (Red Line), AFR held at a very lean ~15.0 in the 2,400 – 3,500 RPM range that decayed to ~13.5 at 5,500 RPM and then ~13.0 at 6,200 RPM. After the tune & a few hours with the tech getting it dialed-in, it was a solid ~13.5 all the way across the board, +/-.1 (Blue Line)
Bear in mind, Harley's OEM spec is around 14.6, which is pretty darn lean & hot to begin with.
Horsepower & torque also improved, but it was the AFR that I wanted to get sorted out.
Red line = Baseline, Blue line = after the tune.
Your results may vary... I REALLY wanted the stock ECU to bridge the gap, I really did. And, for some perhaps it does.
Last edited by FXD_TG; Aug 10, 2012 at 06:08 AM.