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Backfire issue when starting

Have you visually inspected the spark plugs? Maybe check the gap too. Try running some Seafoam through a tank full also.
 
Trapshooter said:
My wife has a 2007 Heritage Softail and about everyother time she starts it it backfires thru the air cleaner. This bike has had the air cleaner opened up and does have a V&H fuel pack installed. I talked to them to see if there was something going on with the settings and they said "no". It also makes a terrible cluking noise when she starts it.

Any ideas what could be wrong?
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Have you done a cold compression test to be sure it isn't a valve problem on start?

Your compensator is causing the bang on start and most all 96 engines do it. It's a very poor design.

Try disconnecting the fueler and see if it still does the pop back on start.
 
Hoople said:
A V&H fuel pack or an EJK? I don't understand which is installed.
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Hoople, my wife's Heritage has a V&H fuel pack on it and is the one in question. I have an EJK on my street glide. Sorry for the confusion...

Glider--I have not done a compression test or disconnected the fueler. I will have to find someone that has a tester to check the compression. I'm don't know much about the fuel pack, can I just unplug it and the bike will revert back to the original settings?

Thanks for the help guys, I will keep you posted.
 
Trapshooter said:
Hoople, my wife's Heritage has a V&H fuel pack on it and is the one in question. I have an EJK on my street glide. Sorry for the confusion...

Glider--I have not done a compression test or disconnected the fueler. I will have to find someone that has a tester to check the compression. I'm don't know much about the fuel pack, can I just unplug it and the bike will revert back to the original settings?

Thanks for the help guys, I will keep you posted.
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Why don't you swap packs and see if the problem follows. JMHO
 
Trapshooter said:
My wife has a 2007 Heritage Softail and about everyother time she starts it it backfires thru the air cleaner.
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During engine cranking, spark advance is backed off but I am sure it is not to 0 degrees or TDC. Therefore any ABILITY to create primary backlash between the crank shaft and starter ring gear (bad spring-pack on compensator) will allow the engine to kick backward for 1 revolution on an unsuccessful engine start. That would absolutely create a backfire through the throttle body. I would bet the engine fires a few degrees before TDC just like it should,, and because of the bad spring stack in the compensator, the engine fires & just kicks back in the wrong direction. All the engine has to do is rotate 50 or so degrees backward and the intake valve will open..
You have a bad compensator that needs to be replaced regardless right?. Change it and see what happens.


I do not think the fuel pack does anything with spark timing. I believe it is only fuel injector changes. If it DOES change spark timing, you need to remove it as a test. But changing only the fuel amount should not make it backfire through throttle body.
Now if the fuel pack DOES change spark timing, then that is a different story.
 
Hoople said:
During engine cranking, spark advance is backed off but I am sure it is not to 0 degrees or TDC. Therefore any ABILITY to create primary backlash between the crank shaft and starter ring gear (bad spring-pack on compensator) will allow the engine to kick backward for 1 revolution on an unsuccessful engine start. That would absolutely create a backfire through the throttle body. I would bet the engine fires a few degrees before TDC just like it should,, and because of the bad spring stack in the compensator, the engine fires & just kicks back in the wrong direction. All the engine has to do is rotate 50 or so degrees backward and the intake valve will open..
You have a bad compensator that needs to be replaced regardless right?. Change it and see what happens.


I do not think the fuel pack does anything with spark timing. I believe it is only fuel injector changes. If it DOES change spark timing, you need to remove it as a test. But changing only the fuel amount should not make it backfire through throttle body.
Now if the fuel pack DOES change spark timing, then that is a different story.
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Now that makes some good sense to me. It does seem to "kick back" when this happens. I beleive that will be my next project, as you said it needs replaced anyway.

As for the fuel pack. When I talked to the V&H tech guy I asked that very question and he said it has NO effect on the timing and only effects the fuel.

Back to the compesator, should I just go to the screaming eagle or is there another one that will work? She's not going to race it anytime soon...:D
 
I have the SE comp on my "96" Dyna and really like it. But they all have the fret rust issue which is something that needs to be corrected for the SE comp to really be the answer. The thing is you don't have many options or choices. The recent oil channel I drilled in the SE arbor may be working. Have to pull it apart once again after I have a few more miles on the modification.
 
Anyone have a good suggestion on where to get the best value on a compensator kit online. I check Zanotti's $212, HD wants $250.
 
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