I picked up a 01 road king over the winter with 17,000 miles on it. It is a 88 fuel ingection and is stock. The bike runs really well, but with myself and my wife, I'm consistly getting 33 mpg. Must less than my old 89 FXR. Is this in the normal range? I've checked the plugs and they are a little dark from fuel but not much. I've checked the brakes to make there wasn't any dragging. I've considered changing pipes, but I do admit this bike is quiet which I do appreciate after the FXR. Would one of the programmers help? Compression appears good, but I have not but a gauge on it yet. I just want to make sure I don't have anything potentially serious.

 

No, that's not normal. The Road King should get around 40 mpg, if not more. Check both your hot and cold idle, and make sure they're properly set. If you don't have the service manual, you should get one. It's a good investment.

Uncle Peepers

 

01 is a Magnetti-Marelli ECM, with a Dual Plenum Runner.....

As time progress' these systems begin to fail, and sometimes the DTC generation is masked....

Long story short... Get it to a reputable shop that has the Computer Diagnostics and get it "Scoped"....

Also, the Service manual will not tell you how to PROPERLY ADJUST the Hot and Cold Idles on your bike.....

You do need the Service Bulletin, and a Digital Tech to do it...

Get the Service manual though, as U/P stated, it is an investment.....

I would venture to say that you might have an I.A.C. issue... These systems eat them up...

 

Quick question- what does "DTC generation is masked" mean, and what's an I.A.C. ?

I've got the MM on my 2000 RK, so I was just wondering.

 

DTC Masking = Diagnostic Trouble Code Generation Problems

I.A.C.= Idle Air Controller (Stepper Motor), Controls Inlet Air upon Start up, Two Way motor, Fails and leaves no codes....

 

Thanks.

 

I was trying to keep it simple without getting into a lot of the "how-to's" on idle setting; that would come after the purchase of the service manual. I've seen a bunch of different ways to set the MM idles in addition to those in the manual and the tech bulletin. I'm sure you have too. The one I finally settled on (as being the most consistent) isn't in any manual. MM's can be quirky.

While I've got you one the line, when the stepper motors fail, in your experience does it happen gradually or do they konk all at once? Also, I just saw a new product from Horsepower, Inc. It's a new throttle body to replace the MM's that incorporates the single runner design and can use the stock ECU. The cost is $875, which is a little steep, but using the $100 per hp standard and figuring you're also getting a more consistent idle, it might be worth it. Do you have any familiarity with this item.

Thanks,
Uncle Peepers

 

I HIGHLY recommend HPI's product line!!!!!!!

Good guys up in Erie.....

One is a former Marine (Don't be a hater for that...!!!!)

Yes, gradual is more the norm in the failures.....

The gears will run down before the windings fail.....

What get's MOST people in trouble is manipulating the TP sensor, and trying to get their Hot to where they WANT it.. (Didn't say where it HAS to be...)

Guy that used to work for JJ at WCC taught me a real slick trick on how to do it, and you still utilize most of the ServBull steps, and get a MUCH BETTER result.... Stock only... Stage you still go by ServBull...

 

Thanks for the response and help. I do have a service manual and it did not have much on the FI. I will take it in and get it scoped. Again thanks

 

Additional Questions..from your responses, I assume that the problem might be a failed idle speed control actuator or improper cold and hot idle settings. Did I understand correctly? I also see that adjusting the throttle position sensor is somewhat difficult, at least according the service manual. I do not detect any problem with the idle settings...bike starts, idles, and runs very well. What would the operation symptom be of a bad idle speed control actuator? Just out of curiousity, where does one obtain a HD 41198 breakout box...guess I could make one if I can find the connectors.

again thanks for your help and education