Secondary Air Injection Question (carbed '05 Bonnie)

Discussion in 'Bonneville' started by daytona2011, Jan 11, 2020.

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  1. daytona2011

    daytona2011 New Member

    Jan 11, 2020
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    #1 daytona2011, Jan 11, 2020
    I have a friend with a 2005 carbed Bonneville, and she noticed that a vacuum hose connected to a fitting on top of the intake manifold had rotted and broken apart. From what I've been able to piece together it's part of the secondary air injection, and in all of the parts diagrams I've been able to find they're just capped, there's not a line going to them at all. So two questions:

    1) Am I correct that those are what open the reed valves for the SAI circuit? If not, what are they?
    2) Assuming it Is part of the SAI, is it OK to just pull the hose off of both sides, cap the fittings on the manifolds, and plug the hose ends? I know there are kits to fully replace everything, but I don't think she wants to go through all of that right now.

    EDIT: I should probably add that I haven't seen it personally yet, so I don't know where the other end of that line currently goes. I asked her when she mentioned it to me, but she wasn't sure.

    82081289_836905030101114_4353012640839106560_n.jpg
     
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  2. Callumity

    Callumity Elite Member

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    #2 Callumity, Jan 11, 2020
    That doesn’t look standard. The SAI is in the cylinder head next to the plugs. Those vacuum nipples should simply be capped. I would be curious to see where that ribbed hose goes!
     
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  3. Sprinter

    Sprinter Kinigit

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    #3 Sprinter, Jan 11, 2020
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  4. capt

    capt Elite Member

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    #4 capt, Jan 11, 2020
    As sprinter said , those studs should be capped ! On early carbureted bikes they are used to "vacuum balance" the carburetors , on later fuel injected bikes they are used by the ECU in conjunction with oxygen sensors in the exhaust headers and temperature sensor and a Mass Air Flow sensor to manage fuel and ignition !

    That bike needs serious maintenance ! There is or has been fuel leakage !
     
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  5. Tom Gillam

    Tom Gillam Guest

    #5 Tom Gillam, Jan 12, 2020
    As Callumity says,they are vacuum nipples that should be capped and are used to balance the carbs.
    As for the other ribbed tube,that is part of the SAI ,but it would be worth considering getting rid of the SAI.
     
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  6. Tom Gillam

    Tom Gillam Guest

    #6 Tom Gillam, Jan 12, 2020
    Apologies the SAI seems to be capped,so not sure about that ribbed hose either.
     
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  7. capt

    capt Elite Member

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    #7 capt, Jan 12, 2020
    Possibly California fuel vapours recovery system ?

    Wild guess !
     
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  8. daytona2011

    daytona2011 New Member

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    #8 daytona2011, Jan 12, 2020
    Most of the bikes I work on are old Hondas, so I'm familiar with carb balancing. That was actually my first thought for those, but I had/have no idea why there's anything connected or where they're going. I'll report back if I get a chance to lift the tank and see what's going on.
     
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  9. Callumity

    Callumity Elite Member

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    #9 Callumity, Jan 12, 2020
    Makes sense but the perished fitting will now make the bike appreciably lean on the LH cylinder and make for lumpy running. Just capping it will be an effective short term fix.
     
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  10. daytona2011

    daytona2011 New Member

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    #10 daytona2011, Jan 13, 2020
    It gets worse...I was just chatting with my friend who owns the bike, and she went out to look at it and found that the port on the right side is already capped. I can't even.

    82093375_784861111984507_4924986913254801408_n.jpg
     
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  11. Mark Sansom

    Mark Sansom New Member

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    #11 Mark Sansom, Jun 9, 2025
    I have exactly the same problem!..capped. Cleaned reed valves and checked all other hoses.
    Still misfires.
     
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  12. joe mc donald

    joe mc donald Joe
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    #12 joe mc donald, Jun 14, 2025
    @Callumity The ribbed hose is snapped and simply fits on just in front were it was originally
     
  13. joe mc donald

    joe mc donald Joe
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    #13 joe mc donald, Jun 14, 2025
    @datona2011 Yes one side is is capped the other is a vacuum for fuel delivery.
     
  14. Regit nogara

    Regit nogara Active Member
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    #14 Regit nogara, Jun 14, 2025
    Hi Joe, this is an old thread. I get misled with old threads many times, not looking at the date. Still a learning curve for some.
    Tony
     
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  15. joe mc donald

    joe mc donald Joe
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    #15 joe mc donald, Jun 14, 2025
    @Regit nogara Boy you are very right on that on. Still nice to chat.
     
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  16. Regit nogara

    Regit nogara Active Member
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    #16 Regit nogara, Jun 15, 2025
    Joe, chatting is good for the soul and mental state.
     
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  17. joe mc donald

    joe mc donald Joe
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    #17 joe mc donald, Jun 15, 2025
    @Regit nogara You are so right. It is the fact i now answer myself as well
     
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