Poor Gas Mileage and dirty pipes

I own a 2005 Dyna Low Rider with approximately 6200 miles on it. I wanted to see if someone could comment on the following issue that has become more apparent as of late.

Approximately a year ago, I had the muffle plates removed from my stock pipes, followed by a Stage 1 upgrade kit and a remap of the EFI. This was all done at an authorized HD dealer in Sellersville, PA.

I would mostly take two to three hour runs, but just last week, I decided to visit the York, PA Vehicle operations plant and go for a tour with some friends. This meant that we would ride about 160 miles to our destination from NJ. Bike ran relatively well, until I started to notice that I was in need of gas. The bike was also running pretty hot, even though we were cruising on the highway.

When I was refuleling, one of my friends decided to get down and look at my pipes, they were coated with soot or carbon type material, which meant that my bike was running too rich. We seemed to agree on the fact that the gas mileage for this bike was pretty low and the fact that it was really hot (temperature wise) comapred to the two Road Kings that were with me. I have contacted the dealer, who has told me that there may be a problem with the plugs? I don't think that the EFI mapping has gone away, so I am trying to find out more information, before I have the bike dyno tested/tuned.

I will appreciate your comments.

Regards,
German

First thing, like chuck said, check air cleaner.

Then check the plugs. Do they both look fouled or just one. Could be a bad injector they can stick on. This doesn't happen often and is way out in left field, but it could happen.

Could be a bad throttle position reading. This may not trip a engine light unless it is out of range for the reading. It may be telling the processor that you are opening the throttle more than you really are. Have HD check this.

Could be a bad coil , but you would probably feel this and is usually all or nothin.

Could be a bad fuel regulator that would allow full pressure from the pump. Have HD look at this too.

Did you put diesel in it ? OK now I'm stretching. I can never stay focussed.

Tom,

Thanks for the great commentary, I will do all the checking that you are referring to, and I'll have my dealer check the most difficult itmes on the list.
Actually they suggested that I perform a Dyno test, what do you think of that?

I was just trying to figure it out here, another words see what comments I get and from there, take the bike to the dealership and solve the problem. I did not want to ride in blindfolded and have them tell me, why my bill was so high afterwards.

Regarding Diesel.... I always try to stick with 91 Octane, so as to keep my injectors clean.

Thanks again.

Regards,
German

G,
All you can do is check the simple things like the air cleaner and plugs. Check the gap on the plugs, make sure they are not broken. stuff like that.

While you have the air cleaner off check for loose throttle parts. You have the return mechanism on the right side and the throttle position sensor on the left. make sure the sensor bolts are tight.

Unfortunately after that you do have to take it to the dealer, but they should put it on the scanner and look for the simple things first before they go to the extreme of loading it on the dyno. That's my 2 cents on the dyno thing.

Sorry G, I just saw this and got your PM. These guys are all on the ball and they have you headed in the right direction. It has to be something restricting the amount of air into the motor in order for it to run rich like that, especially out of the blue. I'm not so sure of the clogged fuel injector as I think that would cause a decrease in fuel delivery but I may be wrong about that, remember my bike is carbed, and I am certainly NOT an EFI guy. (of course after I re-read Tom's post of the injector getting stuck ON that makes sense) Check those obvious things and if all else fails take it to the dealer. I know that sucks to do but sometimes it has to be done. Wait, are you under warranty?? If not, call Rob @ USA cycles. I'll PM the number so as not to get into a spam issue or anything. Good luck, Chris

Hey German...are the fouled plugs wet from fuel or oil?

As to a Dyno run, I'm a big fan of 'em. But a run before resolving the main issue seems premature - Dyno runs are more useful when fine tuning for best performance, IMO. Not that they aren't great to troubleshoot with, but they usually aren't needed for that...and they cost money. So I say Dyno it once you're pretty sure you have it fixed, unless they're gonna pick up the cost for you....and figure the odds of that!

Not Good Man

It's in the shop

Thanks to voodochild, I was able to hook up with USA Cycle here in NJ. The bike will be going through a check up, just to see if we can pinpoint the cause of the poor gas mileage.

As an update, I have replaced the original plugs with a pair of screaming eagle EX12S. The bike immediately felt faster and ran smoother. I am not saying, that I am out of the woods yet, but that's why it is at USA Cycle, for diagnosis.

As an aside, after diggin' some more with the dealer that did the upgrade of my stage 1 kit, I was told that if the mechanic does not feel that he has to do an EFI remap, he just does not do it. Isn't that great? My EFI was "never remapped"

The plot continues....

We shall see.

Regards,
German

German and I went on the Rolling Thunder run this past Sunday. The bike seemed to run fine, although we lost each other later on in the run so we didn't get to talk about how it was in the end. Did you ever get a chance to pull the plugs after the run? I realize the bike is at USA now, but I wonder what they looked like after that run. Any update on that German?

Plugs had a small build up of carbon deposits

voodchild,

Yes I did remove the plugs after the ride and in comparison, the plugs had already begun to build up a small amount of carbon deposits.

I rode the bike to the shop and left it there with Rob, he will be looking into it today and will let me know later, what he has found. He will concentrate on the throttle body or perhaps the fuel injector itself.

As I indicated before, I was very puzzled as to why Dean's Harley Davidson in Sellersville, PA did not remap the EFI? That in itself may be the root of all the problem. If Rob has to install power commander, so be it, so long as that is the only issue.

I will inform later as to the final outcome on this.

German

Final Update

chucktx,

The bike feels a whole lot better, I can't comment on the mileage yet, perhaps with luck, I'll get out this w/e and report later. I rode approximately 30 miles, "taking the long way" home and it felt pretty good.

Thanks again to all of you for your comments, every single one of them had some validity!

Regards,
German

Glad to hear she's back up and running German, and also glad that Rob got ya fixed up. He's an awful nice guy. (did you get to see any of the customs he's building back there??!) Get some ridin in and let us know how it's going.