backfire help please

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Oct 9, 2010 | 05:52 PM

mattman89

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backfire help please

i think my bike is running rich? when i get off the throttle it tends to back fire every few sec. till i pull in the cluth. how do i adjust it? its an 05 harley sporty 1200c, its still has a warrenty though. should just take it in and pay the 50$?

Oct 9, 2010 | 10:55 PM

WRAITH

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From: Mission,BC.Canada

We need more info. What have you changed (exhaust, intake)? Also, pull your spark plugs. What color is the electrode insulator? Back= Fouled (to rich or to much choke). White= To lean (the front cylinder should be off white. Tan= Just right (normal for rear cylinder).

Oct 10, 2010 | 08:38 AM

mattman89

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it has se pipes and the intake has the k and n air filter. im goin to pull the spark right now thanks.

Oct 10, 2010 | 08:55 AM

CheezHead

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From: Wisconsin

Decel back fire is caused by being lean on the primary some call it the slow jet (not the main jet). Go up 1 or 2 sizes and the it will go away.

Oct 10, 2010 | 09:19 AM

mattman89

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ok so i pulled them, the front has a tiny bit of black, but mainly tan. the back is barley tan...

Oct 10, 2010 | 09:39 AM

cHarley

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From: Boynton Beach, FloriDuh

I'm assuming that you acquired this bike used?
A K&N filter in the stock filter can does not produce a significant increase in intake airflow. However, a K&N filter in an SE can does, and would call for an increase in the Pilot (slow) jet size.
The stock pilot jet size is a #42. If you have an SE filter can and the SE pipes, you'll probably need a #45 pilot jet.
Your dealer service department should be able, with just a quick look, to tell you what type of filter can is installed on the bike.

Oct 10, 2010 | 01:51 PM

mattman89

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yep got it used. i also have to bring it in for the 15,000 ,mile service. the dealer said it would be about 325$ for the service. is that expensive or normal for a stealer?