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Hi Guys, I have replaced the rocker cover gasket on my 2010 CB1100 and decided to take apart the reeds (unsure what they are actually called) to see what they are and clean them, As you guys will be aware to get the rocker cover off I had to take out the coils and remove a few other things, well I have put everything back together and triple checked the plug lead order and coil wire order but the bike is idling fairly smooth except it backfires when revved, I went back to google and looked at a wiring diagram to check I have the wire in the correct position and can't find a fault, could it be I have those reed valves in backwards? would that cause a backfire when it's revved or am I missing something with the coils etc, many thanks
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Those reed valves are Honda’s PAIR system—Pulse Secondary Air Injection
To paraphrase from the service manual— pulse secondary air supply system introduces filtered air into the exhaust gases and changes a considerable amount of hydrocarbons and CO to C02 and water.
The fresh air promotes burning of unburned exhaust gases to do the above.
The reed valve prevents reverse air flow through the system. The PAIR control valve is operated by the solenoid valve which is controlled by the PGM-FI unit. The valve is opened/closed depending on the running condition.
The book has a very nice diagram of how everything flows. If you need it, PM me with you email and I will send it to you. We cannot post copyrighted material on the board.
I would first check that all the hoses are correct and the PAIR control solenoid valve is electrical connection is plugged in.
I’ve never had the reeds apart but the book pics look like they really can’t be installed wrong. I may be wrong through. Here is a link to an exploded view
https://www.partsfish.com/oemparts/a/hon...head-cover
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Thanks for the reply Lord Popgun,
I have installed the pair system valves correctly thank you for the diagram, I have just been for a short ride and the bike is misfiring badly, I have spark in all 4 cylinders, it idles smoothly though and only runs rough when throttle is applied, I have not touched the fuel system except removing the fuel tank and disconnected the fuel line and electrical plug for the pump etc, stored the fuel pump carefully while it was out, Does the fuel system need "bleeding" could there be a possible airlock? thanks
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There is no fuel bleeding needed.
OK, assuming you have everything hooked up correctly, you may have mashed the vent line when you replaced the tank. Wouldn’t be the first time it’s happened.
You can open the fuel cap and see if the bike runs ok. If so, then you just find where the vent line is pinched.