02 Road King Rough Ilde

[Bubbat450]

Hello I need HELP... I have an 02 Road king PI when it is idling it shakes the bar so bad you can't stop it with your hands. It shakes the bags really bad too. It is idling at about 1100 to 1200 looking at the tach. If I open the throttle just a hair it gets better. It idle like this all the time. I replace the front motor mount and it shakes just is bad. Can anyone HELP???

Bubba T

 

[Bubbat450]

02 Road King PI Rough Ilde

Well I hate to reply to my own post but I may have the answer. Yesterday on my way home from work I stopped at a red light and the bar had stopped shaking. I was looking to see if I could turn and just figured it's my imagination. Well at the next light it did it again but the light turned green before I could really test it. So as soon as I turned onto my street I put her in neutral and slammed on the brakes. I was amazed. The bars where not shaking and the bike was idling at about 900 to 950 (looking at the stock tach). A Few more miles and it was up to 1,000 and shaking again.

Anyone know what might cause this?

Friday I put a Big Sucker air filter on it. I rode it Friday, Monday and Tuesday to work with no change until I was on my way home.

 

[glider]

Re: 02 Road King PI Rough Ilde

Well I hate to reply to my own post but I may have the answer. Yesterday on my way home from work I stopped at a red light and the bar had stopped shaking. I was looking to see if I could turn and just figured it's my imagination. Well at the next light it did it again but the light turned green before I could really test it. So as soon as I turned onto my street I put her in neutral and slammed on the brakes. I was amazed. The bars where not shaking and the bike was idling at about 900 to 950 (looking at the stock tach). A Few more miles and it was up to 10,000 and shaking again.

Anyone know what might cause this?

Friday I put a Big Sucker air filter on it. I rode it Friday, Monday and Tuesday to work with no change until I was on my way home.

WOW, at 10,000 on any harley, it surely would shake.

Could be a number of things here. Intake leaks, throttle cables sticking, idle speed screw loose, hard to diagnose on the internet without first trying a bunch of things yourself first and posting the results.Could also be a wiring problem to the injector, they had a few of those too down by the injector, they would break inside the insulation.

 

[Bubbat450]

Oops... Too many 0's. It's not the throttle cables. There is not an idle screw. I now think that it is the ECM. I read in the manual that the ECM controls the idle. The dealer can change it with there Scan tool. I have tried a lot of thinks. I posted to see if anyone may have had this problem.

 

[glider]

Maybe if you posted what you did, we would have a better idea as what to suggest.

You do have an idle stop screw (idle speed, not mixture), it's just not too accessible like the factory wants it to be and shouldn't be tinkered with.
The idle speed is set with the digital tech by the dealer. Just pointing out the possibility of it being loose as in the newer bikes are experiencing.

 

[Bubbat450]

I checked the throttle cables
I checked for air leaks
I checked wiring to the fuel injectors.

Fuel injected twin cams do not have an idle screw. The butterfly valve closes all the way shut and hits a positive stop. There is a throttle positing sensor on the butter fly valve that tells the ECM that you are opening the butterfly and the motor needs more fuel. There is a stepper motor on top of the throttle body that lets in air for idle and start up. The ECM controls the injectors for Idle speed.

I think I will buy intake and throttle body gaskets. Ill try that.

I went to the dealer and the where just plain rude. The said they have never heard of something like this.

 

[glider]

Fuel injected twin cams do not have an idle screw. The butterfly valve closes all the way shut and hits a positive stop.

If you look at that stop there is a hidden idle screw that is capped so you don't mess with it, trust me on this one, been doing this longer than I care to remember.:s

Thanks for the education on twin cam motors too.

 

[glider]

Here's a picture of the "idle screw" I made reference to in the lower right of the picture both capped on the right and uncapped in the left picture:s (yes I know they are not the same throttle bodies) Just posted to show the differences. I use the term "idle screw" for lack of a better term.
There have been some on the newer bikes that have moved from the original factory position causing a higher than normal idle speed. This is why I referred to the "idle screw" in the above posts and not meant to confuse matters that you should use this screw to actually adjust the idle speed.

It's used more so to adjust the value of the TPS and throttle blade position at the factory then it is sealed with a lead plug.

It's not used to adjust the idle speed because the digital tech is needed to do that by setting the desired speed (value) in the ECM, from there the stepper motor takes over to keep the idle speed at the set level bypassing the throttle plate.
Use of this screw after uncapping will set a code (DTC) when the parameters for the TPS are altered and the TPS value will have to be reset to eliminate the code using this as a means to do so if the position has been altered. The TPS is non adjustable on the newer bikes because of the elongated slots in the housing were eliminated with the delphi units over the morelli which was adjustable.

 

[Bubbat450]

Finally!!! I'm so glad to be talking to someone that knows this stuff. I've been trying to figure out what is wrong with this bike for a month. I did not mean to come across like you don't know. I just want some help. When I went to the dealer the guy was really rude and did not want to help. He just said Harley's are supposed to vibrate and I must have put the motor mount in wrong. When I ask about the idle being set by the scan tool he just told me my stock tach is not accurate enough to tell what RPM the motor is idling at. Then he just kept saying "Bring it up here and put it on the scanner" He said this about 4 times like he will put it on there just so he can charge me, not to figure out what is wrong. I’m use to the dirt bike industry where they want to help.

When I put the new air filter on, I looked at the idle screw you are showing me. It doesn’t look like it has ever moved and the butterfly seems to be closed all the way.

After what happened Tuesday on the way home, I'm thinking it is an air leak.

Something I for got to mention, Two weeks ago I changed the plugs and the back cylinder looked lean. Do you think I might have an air leak on the intake of the rear cylinder?

Thanks
Bubba T

 

[glider]

Good possibility that if it looked leaner than the front, it's worth checking it out for a leak. They will usually not look the same anyhow but explore the possibility.

Also don't go just by looks in regards to that "idle screw" there will be no visual signs of it moving if in fact it did. If the idle has changes significantly from where it used to be, then maybe suspect it as a cause but don't move the position of the screw.

You are correct in saying that the tach on the bike is not too accurate. It will vary from the actual RPM set in the ECM in most cases by a significant amount.The dig tech will set it accurately through the ECM.