Engine knocking on an 08

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Quebec FJR

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Feb 4, 2008
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Location
St-Hubert, Quebec
When starting cold engine there is a knocking sound coming from left side of engine. Comes on and off for 3 to 4 second intervals until engine is warmed up. Once warmed up will not do it for rest of day. Anyone have any ideas what could be doing this

 
I've experienced the same thing - 1 or 2 knocks and then it's fine. Sound seems to come from the gearbox area. Anyone have know what it might be?

 
Lean misfire. When cold the bike does not get enough fuel from the injection system to make sure all the cylinders have enough fuel. When warm the fuel atomizes better and it works. Unless you have a PCIII or monkey with the CO levels, it is going to do that.

Ed

 
PCIII fixes it. BTDT. Someone get Ed a gold star. :) I don't know if the explanation is right, but, it did seem to be a lean condition.

Edit: oh, and on the 08, the CO levels apparently don't work like they used to. Mine were all zeroes, and changing them (even to an extreme) did nothing.

 
Last edited by a moderator:
PCIII fixes it. BTDT. Someone get Ed a gold star. :) I don't know if the explanation is right, but, it did seem to be a lean condition.
Edit: oh, and on the 08, the CO levels apparently don't work like they used to. Mine were all zeroes, and changing them (even to an extreme) did nothing.

Could someone explain what a PC111 is.

 
Mine did the same from day one. At 4k miles I replaced the plugs with Iridium. Problem solved! On very rare occations it will do it but cant remember the last time I heard it miss.

 
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