Open or Closed loop?

Reply Subscribe

Thread Tools

Search this Thread

Nov 26, 2012 | 04:29 PM

Reaper22

Thread Starter

Road Captain

Joined: May 2011

Posts: 565

Likes: 2

From: Palmyra Missouri

Open or Closed loop?

2013 ultra with power vision and stock o2 sensors, should this be set to open or closed loop???

Nov 26, 2012 | 05:00 PM

icepick

Cruiser

Joined: Jul 2008

Posts: 233

Likes: 0

From: Mississippi

closed loop, but wait on other replies, but I am fairly certain that I am correct. Generally open loop is without sensors and the ECM maintains a fairly constant air/fuel ration regardless of throttle postion, air temp, etc, etc

Nov 26, 2012 | 05:09 PM

UltraNutZ

Extreme HDF Member

Joined: Nov 2007

Posts: 14,670

Likes: 139

From: East of the Sun, West of the Moon

all depends on what you want to accomplish. You're better off posting this in the PV area of the tuning section
https://www.hdforums.com/forum/elect...-by-admin.html

Nov 26, 2012 | 05:51 PM

Mr HOG

Road Master

Joined: Apr 2010

Posts: 824

Likes: 2

From: O'fallon IL

If you are running 02 sensors then closed loop.

Nov 26, 2012 | 05:54 PM

VTL nut

Road Warrior

Joined: May 2009

Posts: 1,537

Likes: 4

From: The Great River Road, Wisconsin

Closed loop will give you the most accurate driveability.
As mentioned, open loop will run blindly on default values.

Nov 26, 2012 | 10:34 PM

iclick

Extreme HDF Member

Joined: Sep 2005

Posts: 11,615

Likes: 50

From: Baton Rouge, LA

I run in open-loop with the PV mostly because I have wideband O2 sensors installed for tuning. I monitor Lambda (AFR) in real time and find that AFR stays ±2% most of the time, averaging ±1%, regardless of environmental conditions. The various sensors on the bike--MAP, IAT, ET, etc.--combine info to keep things remarkably close to where you set them in the AFR table. It is more accurate than most people think and the ECM is not running "blind." It also doesn't run a "constant AFR," and in my case it varies from 13.0-14.5:1 depending on the area of operation.

However, if I had the stock O2 sensors already installed I would use them, as they will probably keep AFR even tighter, though likely not enough for you to notice. The downside to this is that you must keep Lambda no lower than .981 (~14.4:1), as below that exceeds the range of the sensors and the ECM won't allow it. If you set it below that value it will automatically revert to open-loop mode.

Some think that running that lean creates unnecessary heat, but my tests with the PCV-AT toggling between normal and richer maps indicates that it makes little difference in ET (Engine Temp. reported by the on-board CHT sensor) or OT (oil temp.).

Last edited by iclick; Nov 26, 2012 at 10:39 PM.

Nov 27, 2012 | 04:56 PM

Reaper22

Thread Starter

Road Captain

Joined: May 2011

Posts: 565

Likes: 2

From: Palmyra Missouri

Quote:

Originally Posted by iclick

So I can use the autotune feature as long as the lambda is no lower than .981 well here is how my tune was set up, or do I just leave it closed loop? Thanks for your time man... Sorry couldn't get top line moved over on top of column in the correct place..

Fuel\Air-Fuel Ratio (Lambda)
20 30 40 50 60 70 80 85 90 100
750.000 0.981 0.981 0.981 0.981 0.981 0.981 0.981 0.890 0.869 0.869
1000.000 0.981 0.981 0.981 0.981 0.981 0.981 0.981 0.890 0.869 0.869
1250.000 0.981 0.981 0.981 0.981 0.981 0.981 0.981 0.890 0.869 0.869
1500.000 0.939 0.981 0.981 0.981 0.981 0.981 0.981 0.890 0.869 0.869
1750.000 0.939 0.981 0.981 0.981 0.981 0.981 0.981 0.890 0.869 0.869
2000.000 0.939 0.981 0.981 0.981 0.981 0.981 0.981 0.890 0.869 0.869
2250.000 0.939 0.981 0.981 0.981 0.981 0.981 0.981 0.890 0.869 0.869
2500.000 0.939 0.981 0.981 0.981 0.981 0.981 0.981 0.890 0.869 0.869
3000.000 0.939 0.981 0.981 0.981 0.981 0.981 0.981 0.890 0.869 0.869
3500.000 0.939 0.981 0.981 0.981 0.981 0.981 0.981 0.890 0.869 0.869
3750.000 0.939 0.981 0.981 0.981 0.981 0.981 0.981 0.890 0.869 0.869
4000.000 0.939 0.981 0.981 0.981 0.981 0.981 0.981 0.890 0.869 0.869
4500.000 0.890 0.890 0.890 0.890 0.890 0.890 0.890 0.890 0.869 0.869
5000.000 0.890 0.890 0.890 0.890 0.890 0.890 0.890 0.869 0.869 0.869
5500.000 0.890 0.890 0.890 0.890 0.890 0.890 0.869 0.869 0.869 0.869
6000.000 0.890 0.890 0.890 0.890 0.890 0.869 0.869 0.869 0.869 0.869
6500.000 0.890 0.890 0.890 0.890 0.890 0.869 0.869 0.869 0.869 0.869

Last edited by Reaper22; Nov 27, 2012 at 05:16 PM.

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

Engraved Rebellion: Inside Bundnerbike's Glam Rock II

Verdad Gallardo

10 Motorcycles You Should Never Buy

Joe Kucinski

10 Things Harley-Davidson Needs to Fix in 2026

Verdad Gallardo

Southpaw Super Glide: A Left-Hand-Drive 1979 Harley FXE Built to Fit the Rider

Verdad Gallardo

Nov 27, 2012 | 06:36 PM

iclick

Extreme HDF Member

Joined: Sep 2005

Posts: 11,615

Likes: 50

From: Baton Rouge, LA

Quote:

Originally Posted by Reaper22

So I can use the autotune feature as long as the lambda is no lower than .981

You don't run in closed-loop to tune with PV, but disable it in the ECM so the O2 sensors can provide info for the datalogs. With the stock NB O2 sensors you can only tune in a very narrow range from about .981-1.02. If you are using Autotune Pro with the AT-100 kit (wideband O2 sensors) you can set Lambda most anywhere you want, as these sensors have a much wider range of operation. Once the tuning is done you can optionally turn CL back on if you're tuning with the stock narrow-band O2 sensors. With the optional widebands you have no choice but to tune and run in open-loop, that is unless you switch to the narrow-bands after tuning.

Quote:

well here is how my tune was set up, or do I just leave it closed loop? Thanks for your time man... Sorry couldn't get top line moved over on top of column in the correct place..

I would post this type of question in the PV sticky thread where lots more people can offer their advice. I tune the old-fashioned way with WinPV and PVTune, but Autotune simply does the entire procedure in the PV itself, starting with turning off CL, datalogging, and compiling the data to produce a new tune. Once that is done it places it in one of the six tune slots available on the PV, and you're final step is to flash it to the ECM.

Regarding your posted tune, the .981 numbers represent the lowest Lambda values the ECM will accept to run in CL. Anything below that (or above 1.02) will force open-loop.

Last edited by iclick; Nov 27, 2012 at 06:57 PM.

Nov 27, 2012 | 06:46 PM

#10

Reaper22

Thread Starter

Road Captain

Joined: May 2011

Posts: 565

Likes: 2

From: Palmyra Missouri

Quote:

Originally Posted by iclick

You don't run in closed-loop to tune, but cut it off in the ECM so the O2 sensors can provide info for the datalogs. Once the tuning is done you can optionally turn CL back on, that is if you're tuning with the stock narrow-band O2 sensors. With the optional widebands you have no choice but to tune and run in open-loop, that is unless you switch to the narrow-bands after tuning.

I would post this type of question in the PV sticky thread where lots more people can offer their advice. I tune the old-fashioned way with WinPV and PVTune, but Autotune simply does the entire procedure in the PV itself, starting with turning off CL, datalogging, and compiling the data to produce a new tune. Once that is done it places it in one of the six tune slots available on the PV.

The .981 numbers represent the lowest Lambda values that the ECM will accept to run in CL. Anything below that (or above 1.02) will force open-loop. You might find it better to taper the values a bit from 80-100 KPA, as right now you are coming off about 14.4:1 to ~12.7:1 really quick. From 2000-4000 rpm I would do something like .981 @ 80kpa, .95 @ 85kpa, .92 @ 90kpa, and .89 @ 100kpa. You could stick with .869 @ 100kpa, but I think that's a bit rich since max power should be around .89 (13.0:1). Where did these values come from? Original tune?

Jamie at Fuel Moto when I bought my tune package...

Reply Share

First
Prev
1 / 2
Next
Last

Forum Jump

Open or Closed loop?

Open or Closed loop?

Trending Topics

7 Surprising Harley-Davidson Products that Are Not Motorcycles

8 Best Harley-Davidson Motorcycles Ever

10 Worst Harley-Davidson Motorcycles Ever

Killer Custom's Jail Break Is The Breakout That Refused to Blend In

Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?

Harley-Davidson Reveals Super Cool Cafe Racer Concept

Engraved Rebellion: Inside Bundnerbike's Glam Rock II

10 Motorcycles You Should Never Buy

10 Things Harley-Davidson Needs to Fix in 2026

Southpaw Super Glide: A Left-Hand-Drive 1979 Harley FXE Built to Fit the Rider