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Hi All. I read this post with great interest because my bike makes the same clicking noise, and it comes and goes. I thought it might have been a fuel injector noise, but it appears that it might be a reed valve. I have a couple of questions:
1. Are the "smog valves" GAVSP1 is referring to the "exhaust reed valve" that Max is referring to? Is the "pair valve" Max is referring to the "Air Injection Control Valve" (36172-MCA-A62)? I am looking at the Illustrated Parts Breakdown and I do not see an O-ring associated with the Reed Valve (part number 18601-KEA-741).
2. The Illustrated Parts Breakdown illustration shows only two reed valves and two plates (12341-MAT-750) , but defines a quantity of four reeds and four plates required. Are there actually two reed valves and two plates installed into each reed valve cover?
Thank you for the clarification.
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Dave, the Air Injection Control Valve is for purging the charcoal canister. Its part of the evap. emissions system.
As far as the diagram showing 2 and saying you need 4. Look closely at the space the reeds go in. There are 2 spaces per side. So 4 number 8 and 4 number 5 are needed.
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(03-16-2021, 09:30 PM)Lord Popgun_imp Wrote: Dave, the Air Injection Control Valve is for purging the charcoal canister. Its part of the evap. emissions system.
As far as the diagram showing 2 and saying you need 4. Look closely at the space the reeds go in. There are 2 spaces per side. So 4 number 8 and 4 number 5 are needed.
Thank you Lord Popgun. Maybe somebody else can reply concerning the O-ring.
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Dave, I made a mistake above and would like to correct it.
The Air Injection Control Valve in the parts fiche is called the Pair Control Solenoid Valve in the service manual.
The canister purge valve is referred to as the Evap Purge Control Solenoid valve in the manual.
The Evap valve has 2 hose connections. The PAIR valve has 3.
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(03-17-2021, 02:00 AM)Dave_imp Wrote: (03-16-2021, 09:30 PM)Lord Popgun_imp Wrote: Dave, the Air Injection Control Valve is for purging the charcoal canister. Its part of the evap. emissions system.
As far as the diagram showing 2 and saying you need 4. Look closely at the space the reeds go in. There are 2 spaces per side. So 4 number 8 and 4 number 5 are needed.
Thank you Lord Popgun. Maybe somebody else can reply concerning the O-ring.
From my recent 2014 CB1100DX experience only parts involved are:
1. VALVE, REED (ARAI) 18601-KEA-741 qty=2
2. PLATE, PORT (AI) 12341-MAT-750 qty=2
I did not have to replace them. They cleaned up just fine with white vinegar.
There is no O-ring for this assy.
The valve cover assy has 4 O-rings (GASKET B, HEAD COVER 12396-KCR-940) assoicated with it but you don't need these unless you remove the valve cover.
*
IMPORTANT NOTE: Removing the Reed Valve Cover exposes the Reed Valve which has a very deceptive brass screw head showing. Don't attempt to remove the screw ... it is not meant to be removed! The whole rubber/metal Reed Valve assy just pops out, BUT not easily because of all the carbon build up. I cheated when I had the valve cover off by using compressed air to blow it out.
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Glad I saw this post. My 2013 CB1100 also makes a slight ticking sound I hear only when the bike is in a quiet mode, like slowing down or not accelerating. My hearing is excellent, so I know it is there, but still a funny sound.
(03-16-2021, 03:10 AM)max_imp Wrote: Our Australian friend found the missing link ( o-ring ) i think.
Since the variable ticking sound disappeared when the combustion stopped ( sparkplug disconnected ) it is likely that the
exhaust reed valve seal is not working properly.
The pair valve system works on the principle of mixing air into the exhaust system by letting some air into the exhaust through a one way reed valve into the exhaust port using the "vacuum" that happens after the ex valves close and the shockwave makes it's way down the exhaust pipe, the resulting under pressure " sucks " some air past the reed valve and dilutes/ combusts the mixture resulting in cleaner exhaust emissions for the purpose of passing emission regulations.
The two openings to the exhaust channels can be seen in the picture between the spark plugs and the back of the rocker cover just outside of the tappet cover seal and will have an o-ring each in the tappet cover leading to the two reed valves bolted to the top of the valve tappet cover.
To test this you could use a plastic hose and listen to these openings for gas escaping here.
Second possibility is a faulty reed valve, this can be checked by inspecting the valves by removing the two bolts that hold the " flapper valve " housing to the tappet cover, these valves are meant to stop exhaust gas escaping through the air injection system, if a reed valve is not working it should be obvious by removing the rubber air hose to the flapper valve housing.
Question; has the tappet cover been removed in the past?
Very interesting find here GAVSP1, thanks for your help.
And thanks bflint for your update, appreciated.
Hi, anyway to mark the area in the photo you are talking about. I do not know the internals of this engine well enough to be sure I am looking at the right spot. Thanks, Michael
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Michael, Look at the pic in post 19 of this thread.
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(03-17-2021, 11:19 PM)Lord Popgun_imp Wrote: Michael, Look at the pic in post 19 of this thread.
Thanks! My bike is not making the sound as loud as the bike in the video does, and I only hear it when the bike is running quietly. Does anyone believe this ticking sound is going to hurt the engine? Mine is so quite, I am not sure if I should be worried about it right now.
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Are you sure it's not just the injectors clicking away normally?
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Thanks! My bike is not making the sound as loud as the bike in the video does, and I only hear it when the bike is running quietly. Does anyone believe this ticking sound is going to hurt the engine? Mine is so quite, I am not sure if I should be worried about it right now.
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The ticking sound in my bike comes and goes. I can only hear it when the engine is idling, as it stops when the RPMs are increased. Sometimes it is louder than other times. I thought it was the fuel injectors clicking. The next time I hear the clicking I'll use the old screwdriver to the ear trick to see if I can better locate it. I performed the screwdriver test and inspected the area near the counter balancer adjuster, and determined the sound was not coming from that area. I did inspect at the fuel injectors and thought the sound was coming from that area, but now I want to inspect the area at the reed valves to be certain. I love the way the members of this forum all join in to help each other to resolve our little issues!
