King cat backfire

Jan 22, 2016
39
2
8
I have an 05 king cat 900 EFI, when i start it up cold it idles for a bit then backfires once and continues to idle fine. I have checked ground wires and connections. I was told a backfire can crack or break the reeds. Anyone know what could be causing this? Engine is stock, power valve deletes, v force reeds, a can and boondocker box.
 
Jan 22, 2016
39
2
8
I don't think so, it's done it every ride so far this season, and I fuel up before every ride usually around 10 gallons. It's got non ethanol fuel in it right now too.
 

IDspud

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Lifetime Membership
Nov 26, 2007
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Oakley, ID
Condensation collects as it cools and warms each day inside the tank, adding water. If you don't proactively remove it with heet or similar product it adds up and backfiring is the result.
 

Readymedic

Well-known member
Premium Member
Nov 6, 2013
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Saskatchewan Canada
Try a new set of plugs. I have had brand new plugs that are dead. I have also had plugs that have decent spark outside of the cylinder, but when installed under compression they don't fire and puke, fart and flood and puke out gas from the Y pipe and eventually the pipe.
Check your plug wires too. Those go bad on the older cats. Can even turn off the cap and cut 1/4 inch off so you get nice new wire and turn them back on tight but centered.
FYI.
 
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