13 replies to this topic
  • StPeters21

Posted May 08, 2008 - 06:58 AM


Now we have rules on posting??? Geez :eek:

I having prob with my '06 450. I have a WB complete exhaust system that the packing has worn out. So while V&H is taking over ans won't have packing until late June. I went ahead and put the stock exhaust back on the bike. This thing is back firing like crazy. I checked the exhaust seal and everything seems to be good. I only change out the pilot to a 48 when I put the WB exhaust on it...Am I missing something here??? I just checked the intake valves and they are a little tight ...I mean barely... Would that cause the backfiring like its doing now??? Or do I need to search somewhere else?

  • grayracer513

Posted May 08, 2008 - 09:07 AM


Decel backfire is caused by one of two things; an air leak at the midpipe/header or header/head seals or joints (or a crack), or lean idle mixture. If you're convinced you have no air leaks, try this:

  • Ga426owner

Posted May 08, 2008 - 04:48 PM


Try motosport outlet they had repack kits if this is the issue

  • StPeters21

Posted May 12, 2008 - 05:57 AM


Well...I checked my valves and had a tight intake valves. I fixed that and now it starts better than it ever has....I still have a backfire issue. I checked the seals on the exhaust and it didn't help. Also it shouldn't be a jetting issue. I am going from an aftermarket exhaust to the stock one. I have a 50 pilot in it. I'm kinda lost now... Could it be an intake leak? Like the airboot or something???

  • grayracer513

Posted May 12, 2008 - 06:10 AM


Every once in a while, you get one that pops because it's too rich. Try the process I linked to and see how that comes out. I see no reason to be running a #50 pilot jet.

And the gasket in the exhaust port is OK, you say?

  • StPeters21

Posted May 12, 2008 - 08:57 AM


Every once in a while, you get one that pops because it's too rich. Try the process I linked to and see how that comes out. I see no reason to be running a #50 pilot jet.

And the gasket in the exhaust port is OK, you say?

I live in the midwest and tried a 48 (with the WB exhaust) and it just wouldnt run right. The 50 made it run much better. I will try and go leaner now that I am running the stock exhaust. I didn't know about the "too rich" back firing possibility.

The gasket in the exhaust port is good. That's actually where I went and looked 1st.

  • StPeters21

Posted May 19, 2008 - 05:52 AM


Ok...finished the valve adjustment. This thing runs better than the day I bought it. WOW. It starts with a half a kick. It's awesome!!!!!! Now I think I'm having some carb issues. It just doesn't seem to idle right. It goes from real low to high and no real in between. I'm going to tear it apart and clean it up. See if that helps at all. Any suggestions on what I should focus on would be greatly appreciated...

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  • grayracer513

Posted May 19, 2008 - 09:32 AM


The idle symptoms you describe are usually a result of an intake air leak, tight intake valves, or a lean idle mixture.

  • StPeters21

Posted May 19, 2008 - 10:13 AM


I checked the intake with carb cleaner while it was running. Couldn't find a leak. I just adjusted the intake valves. So the lean idle mixture is all thats left. Like you pointed out earlier...I already am running a #50 pilot...So thats weird??? I am just going to try and go leaner see if I'm getting some weird stuff by being rich???

Thanks Gray

  • StPeters21

Posted May 20, 2008 - 06:33 AM


This thing is really frustrating me. It is really acting like an intake air leak, but I just can't find it. I have a #48 pilot in it now and it runs good. Except I get the flame on decel. I looked at my air filter and its looking semi wore out. So I threw that away and cleaned up a new one. I will oil it up tonight and see if that helps. Other than that. I dont know where else to go????? Exhaust gasket is good and no leaks there....even though thats what its acting like.

  • grayracer513

Posted May 20, 2008 - 08:39 AM


...And you checked the exhaust joint at the head?

  • StPeters21

Posted May 20, 2008 - 08:49 AM


yep. but thats what it's acting like. I don't get it??? should I just get another gasket and start over?

  • grayracer513

Posted May 20, 2008 - 08:59 AM


Might be the way to go. If I read this whole thing right, it started when the exhaust was changed, and unless you went way leaner when you added the WB pipe, nothing else really makes a lot of sense.

  • StPeters21

Posted May 20, 2008 - 09:03 AM


Yes it all started with the exhaust. Thats why I went back there and checked several times. Still finding nothing wrong there. That's why I keep scratching my head and asking questions. I put a clean airfilter on at the same time.. That could have been part of it. But not like this. I will order one today.

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