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whittlebeast
7th January 2007, 01:02
Have people noticed you EFI hunting as you try to hold a very steady speed. This is normally a sign the the O2 feed back loop is adjusting the fuel too much and then over compensating and swinging too far in the other direction. I wonder if this is an issue in all Harley EFI bikes or could be unique to my bike. Does anyone have any idea if these bikes "learn" with time like most cars do? I have very little experance with Harley buy I am a bata tester for one laptop tuned EFI system and have a good feel for what can be done if you have access to the maps.

AW

CBAS5
7th January 2007, 01:06
I think the closed-loop system on the 07 Harley's should "learn". I'm not 100% on that though.

Gary7
7th January 2007, 01:15
I've never noticed any "hunting" on mine.

rharrison356
7th January 2007, 01:18
Have people noticed you EFI hunting as you try to hold a very steady speed. This is normally a sign the the O2 feed back loop is adjusting the fuel too much and then over compensating and swinging too far in the other direction. I wonder if this is an issue in all Harley EFI bikes or could be unique to my bike. Does anyone have any idea if these bikes "learn" with time like most cars do? I have very little experance with Harley buy I am a bata tester for one laptop tuned EFI system and have a good feel for what can be done if you have access to the maps.

AWI have not experienced the "hunting" you mentioned. Nor has this been brought up by members so far, although your post might raise the issue. Could you have an exhaust leak or other variable parameter that is causing the EFI to "hunt" but not enough to set off the Check Engine light?

What tuning system are you using? I hope you will keep us up-to-date on finding. Also, what bike (1200/883).

rharrison356
7th January 2007, 01:21
I think the closed-loop system on the 07 Harley's should "learn". I'm not 100% on that though.When I disconnected the battery after the 1000 miles service I noticed the bike ran very rich for the first twenty or so miles. I figured this was the "default" setting on the EFI similar most cars. If this is the case, it would be important to know for sure, as tuning a SERF, SERT, FuelPak, PowerCommander etc...while running in the "learn" mode would result in false settings and a poor running bike.

whittlebeast
7th January 2007, 02:05
I forgot to mention, I am riding my wifes 2007 1200L. If your bike ran way fat after a reset then the base maps are too rich. Noticing this most likely is a little bit a function of what you are accustomed to riding. If most of your riding is on a carb bike... My other ride is a Honda ST1300. I find it amazing how different the two bikes ride. Neither is hands down better, .... Just different.

I am a bata tester for Megasquirt see msextra.com and msefi.com For some light reading, read the MegaManual.

AW

Screw Loose Dan
7th January 2007, 04:21
I've got over 5300 miles on my bike. A good mix of highway and back roads. I never noticed what you are describing as hunting, but never paid that close of attention. Interesting though, keep us posted.

obiwan
7th January 2007, 12:09
By 'hunting' do you mean the same as 'surging'? My XL50 does that when I'm trying to hold a constant speed around 40mph. But the roads here are so bumpy I can't tell whether it's the efi system or just my throttle hand not being able to maintain the same position.

Here is a quote on the O2 sensors from another site:

When the bike is operated at engine speeds between 2500 and 3500 rpm at road speeds in the 40 to 60 mph range under a steady light load (no down grades or steep upgrades, not decelerating or accelerating) for 30 or so seconds then, and only then, are you operating in "closed-loop" mode, and the O2 sensor inputs will cause a change to the ECU Map programming to attempt to obtain an A/F ratio at or near stoichiometric, or approximately 14.6 parts air to one part fuel. At all other times, the system is in "Open-loop" and the O2 sensors are not being used.

whittlebeast
7th January 2007, 14:02
Yes, by hunting I mean the motor does not want to settle into a constant RPM when going down a slight hill. THe motor would be putting no HP at this point and is just along for the ride. Get into or compleatly out of the throttle and all is fine.

I would be very supprised if the O2's are only used in light cruse. Most likely they are used at any time that the motor is below about 50 percent power. Based on percent torque not throttle position. Dyno operators know this as "at about there the motor should be at about 12.5 to one". Many companys compleatly turn off the fuel when the motor is in a down shift condition. In the Harley world, sound is everything and I dought Harley would do this. EPA may force it though. Has anyone thrown a wide band on one of these thing and watched the AFR on a dyno. It would be great to have a dyno run with the motor rolling in an out of the throttle and recording the AFR to figure out what Harley and Delfi are up to. It's sad but with a Mega squirt I could tune this out in just a few min. My jetski can be tuned from shore as my kids are out on the lake all wirelessly. It makes about 140hp from 800 cc at 7000 RPM pulling air thru a Ford mass air flow. I work a fair amount with the fuel side of the code with the Megasquirt programmers.

AW

obiwan
7th January 2007, 16:00
Yes, by hunting I mean the motor does not want to settle into a constant RPM when going down a slight hill. THe motor would be putting no HP at this point and is just along for the ride. Get into or compleatly out of the throttle and all is fine.
Yes, that's what mine does too. Very annoying, but as I said I just assumed, because the bike has such a sensitive throttle, it was my wobbly hand. Maybe it's a combination of both.

As to the rest of your post, I'm afraid that's way over my head. :wonderlan

tigertamer
7th January 2007, 17:54
[QUOTE=obiwan;598670]By 'hunting' do you mean the same as 'surging'? My XL50 does that when I'm trying to hold a constant speed around 40mph. But the roads here are so bumpy I can't tell whether it's the efi system or just my throttle hand not being able to maintain the same position.

You might be able to rule-out your throttle hand by temporarilly tightening your throttle friction screw and let 'er go at the map load in question!

Gary7
7th January 2007, 22:16
I just don't buy the following quote. My understanding of modern closed-loop EFI is that it operates closed-loop the vast majority of the time.

When the bike is operated at engine speeds between 2500 and 3500 rpm at road speeds in the 40 to 60 mph range under a steady light load (no down grades or steep upgrades, not decelerating or accelerating) for 30 or so seconds then, and only then, are you operating in "closed-loop" mode, and the O2 sensor inputs will cause a change to the ECU Map programming to attempt to obtain an A/F ratio at or near stoichiometric, or approximately 14.6 parts air to one part fuel. At all other times, the system is in "Open-loop" and the O2 sensors are not being used.

obiwan
8th January 2007, 00:02
I just don't buy the following quote. My understanding of modern closed-loop EFI is that it operates closed-loop the vast majority of the time.

Then read the whole article here, it might make more sense:

http://www.jpcycles.com/Shell2.aspx?src=Tech/Articles/TuningFuelInjection.htm

and this one:

http://www.jpcycles.com/Shell2.aspx?src=Tech/Articles/PortFuelInjection.htm

I'm not saying either article is correct, but with the absence of any official documentation from the Moco, it's better than nothing. It would be much better if HD released the information to owners. One assumes it is available otherwise how would V&H & PowerCommander & Dobeck be producing units that plug into the HD ECM?

Stage one on efi Sportys seems to be open to a lot of interpretation, depending on who you talk to, dealers included.

wolvesharley
27th January 2007, 09:34
i noticed the hunting thing on my street bob, also notice it on my car. it seems to happen when you are on a steady throttle . it is as if the efi cant quite make its mind up.

tigertamer
27th January 2007, 16:29
i noticed the hunting thing on my street bob, also notice it on my car. it seems to happen when you are on a steady throttle . it is as if the efi cant quite make its mind up.

The spark advance could be causing this as well.

jumpman
19th July 2007, 17:17
My 07 1200C is in the shop right now for just this reason. With 900 miles on it I am getting 31 mpg as well. Totally unacceptable.

Have been told that this can be fixed by doing a remap. We will see. Also front forks feel like they are shaking themselves loose and brakes are spongy.

NRHS Sales
19th July 2007, 17:23
It is not hunting. It is switching from closed loop to open loop mode and it greatly changes the air/fuel ratio as it does this. On one of the 07 1250 conversions we did for a customer it would result in a 10 hp difference as it switched.

this is the main reason why power commanders eliminate the O2 sensors to prevent this from happening.

idahopilot
19th July 2007, 17:33
Dan, Thanks for that post. I've had a problem with my 07 1200R ever since I bought it. It kind of does what whittlebeast was referring to -- kind of like it's "missing out," some times it will completely misfire. It just doesn't run well at around 2000 rpm. I have yet to do the full stage 1 (pipes only so far) and was hoping this would eliminate the problem. Is a Power Commander the fuel scheduler of choice?

Moved On / My Own Choice
19th July 2007, 17:45
I will continue to say that these motors are not meant to run at 2k rpm!

2.5 is the LOWEST I go, and I don't accelerate from that point.

Keep it at/near 3k or higher and you're not gonna feel this problem.

NRHS Sales
19th July 2007, 17:59
Kev is right about the rpm range. these engines are not happy at 2,000 rpms. I always keep mine above 2700 rpms when cruising.

THEY ARE NOT BIG TWINS, DO NOT RIDE THEM THAT WAY.

I like the power commanders but the SERT also works good.

idahopilot
19th July 2007, 18:13
I will continue to say that these motors are not meant to run at 2k rpm!

2.5 is the LOWEST I go, and I don't accelerate from that point.

Keep it at/near 3k or higher and you're not gonna feel this problem.

Kev, I agree (not that it matters). I stay away from the 2K range now and the bike runs beautifully. I was just glad to that it's a "sportsterism" and not something wrong with my bike (my first Harley). I'm still curious however, if a Power Commander, V & H Fuel Pak, SERT, etc. would eliminate the problems @ 2000 rpm?

Glock Holiday
21st July 2007, 18:08
Perhaps.Harley just doesn't have the 07' FI sporties quite right and they know it.They run too lean and run too hot (internally and externally) and you'll just have to alter the way you ride the thing or you can get an aftermarket fuel controller if you want to and try that.
Just how long do people think this engine will run with the extreme temperatures it runs at? How many years of oil temps in the 220-240 degrees can this air cooled engine take?
That's a big question on my mind. I'm wrestling with selling my bike for that very reason.

JohnBoy1
21st July 2007, 20:14
Before the stage 1 mine would surge trying to cruise at a steady speed, after the pc3 and ditching the o2's it runs preety much even across the board and engine temps dropped alot aswell. 240 before and 200 with stage 1 and syn all around.

Gone
24th July 2007, 04:41
Before the stage 1 mine would surge trying to cruise at a steady speed, after the pc3 and ditching the o2's it runs preety much even across the board and engine temps dropped alot aswell. 240 before and 200 with stage 1 and syn all around.

I haven't measured with a gage, but mine seems to be running a little cooler with synthetic in both sides. I don't get baked quite as bad at stop lights and it doesn't crackle as loud when I shut it off.

ColinB
24th July 2007, 17:57
I've just come back from test-riding my 883R after fitting a Cobra Fi2000R fueler. The bike definitely runs better and stronger throughout the rev range and the hunting that I had on a partially open cruising throttle has gone. It also feels as though it's running cooler, but I've got no figures to back this up with. The rest of the bike is stock. I like the idea of the Fi2000R as it's so easy to fiddle with the three 'jet' controls (it comes set up for the bike) and when I add pipes and air filter next year there's no re-map needed.

If it ever stops raining over here in the UK I'll get some serious miles on it - but it looks like I'll have to escape to France for August.

Colin

Heepster
24th July 2007, 21:59
My 07 1200R hunts/surges also. My son's 07 883R is rock solid, no hunting in any rpm range. 1000 mile service coming up soon, I'll mention it then and see what happens.

whittlebeast
24th July 2007, 22:07
I just purchased a Innovate wideband with data logging including geez, RPM, MAP and AFR. Hopfully we will at least get to the source of the issue soon.

see http://www.innovatemotorsports.com/products/lm1.php

AW

rick szymanski
25th July 2007, 05:29
is it hunting birds, rabits, squirrels, or deer? does it have a license? is it the correct season?




























just playin

easywriter
1st August 2007, 06:23
I'm riding a 07 1200L I noticed the same thing as soon as I picked the bike up. Felt like what we would have called a "lean-roll" on the carb bikes. (Would have just reached down and twisted the air screw on my old bike)Anyway it feels almost like a no-load lean miss. I've got about 700 mi. on it now. And it has either got better... or I'm getting use to it. I was planning to do SE air & exhaust and remap after 1000 mi. I'm hoping this will take care of that. I'ts not bad... but it is there.

jumpman
1st August 2007, 15:52
Mine has done that from day one. Dealer would not look at it when I first reported it as they wanted to see more miles on the bike before they checked it out. Guess they didn't think I knew what I was talking about. When I had 900 miles on it I finally took it back to them and told them to fix it!

The bike was running hot and lean, very lean. Replaced both plugs which were(snow white). Installed Stage one download. And come to find out the intake seals were bad as well. Had to replace them. Was getting 31 mpg.

Document everything! Now I have to worry about what if any internal damage I have from running so lean / hot.

No surge / hunting now and much better pick up. Have also noticed that I no longer feel the heat of the exhaust and engine as I did before. Differance is night and day.

Also had a poor riding front end - Spongy brakes. Addressed all four concerns and bike seems to be running much better.

Jumpman

whittlebeast
1st August 2007, 18:53
White plugs does not supprise me on a motor that spends most of its time with a 14.7:1 AFR. Brown/tan plugs is about the best you could get in the old days of carbs.

Most motors do not like to run on 14.7:1 at idle, 13 or so makes the motor more happy but EPA starts to wine and there is the gist of the EPA / Harley fight. This is mosty likely the real reason for the 1000 RPM idle now. On WOT EPA really doesn't care what the motor does as long as a missfire does not set in and the AFRs are around 12.5 or 13.

The hunting at 2000 - 2400 is a programming issue that can be fixed and is not inherent with 02s. Your car does not do it. Neither should your bike. The 02s do not need to be removed to cure the hunting. Removing them introduces other issues.

RE heat: I think/guess that the raised temps are due to in the old days the motor ran so fat that the mixtures kept the temps down. It was an unintended concequence from fat mixtures.

AW

Moved On / My Own Choice
1st August 2007, 23:26
On the white plugs...

I purposely kept the jetting on the lean side with our 05, and the plugs were snow white too, but oil temps never really exceeded 200F maybe 210F on the hottest day.

It wasn't a problem....

whittlebeast
11th June 2008, 23:44
I documented the EFI causing the hunting. It is appears to be the 02 feedback loop.

We are working on a cheep work around.

http://www.ncs-stl.com/sert/o2s_vs_none.jpg

stevja1
11th June 2008, 23:51
I'm getting my bike remapped on Tuesday with the new exhaust/cams.
Any info that you figure out that I can tell the tech would be appreciated.

Jorg
12th June 2008, 00:29
I have good results with this little cheater from nightrider:

"O2 IED
14.2:1 AFR O2 Sensor Inline Enhancement Device for
2007 H-D
2008 H-D

Nightrider's unique "patent pending" design to quickly and simply improve the closed loop fuel mixture on your TC96/103/110 engine from 14.6:1 to 14.2:1. This results in cooler exhaust temperatures. Recommended for stock bikes and those with upgraded exhaust or intake.

Voltage Output from a typical narrow band O2 sensor
The most accurate range for narrow band O2 sensors is the .400v to .800v or the 15.0:1 to 14.2:1 AFR ranges. Once the fuel ratio is outside these limits, the accuracy of measurement rapidly changes. This is why narrow band oxygen sensor are considered a 14.7:1 AFR voltage switch.

The voltage divider works by taking advantage of the accurate range of the O2 sensor and some simple electronics to allow .750v output from the O2 sensor to look like .500v to the fuel injections system."

jorg

whittlebeast
12th June 2008, 00:51
http://www.hdforums.com/m_2836828/tm.htm

Lots of input but very little documented data.

AW