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Dual Carbs

Discussion in 'Motorcycle Tech Talk' started by JohnnyBiker, Apr 13, 2011.

  1. JohnnyBiker

    JohnnyBiker Well-Known Member

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    On a 1998 Suzuki Intruder (Hot Riders Bike) there are two carbs that have to be synced. OK we all know that. From what I have heard and seems to be a common theme is that the rear carb gets less fuel or receives the fuel last. If there is popping coming from the tail pipe, (which there is), can you re-jet only that carb to compensate for the "starving of fuel" to get rid of the popping.

    One thing that I have noticed with her bike is that it only "pops" up to 60 mph. Once you have hit 60, then the popping seems to go away or happens way less often. This would indicate to me that there is a slow jet issue. Am I am on the right track? Suggestions would be awesome. Thanks JB

    P.S. I forget to add that it is an 800.
  2. FLHTbiker

    FLHTbiker Moderator Staff Member

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  3. JohnnyBiker

    JohnnyBiker Well-Known Member

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    Those are some great pointers for syncing the carbs, but I am more curious about if it is possible or recommended that I use different jet sizes. Example: Carb 1 has a 46 pilot. Carb 2 has a 44.

    The reason I am asking is because the carbs were synced once since we have had it and it did not cure the problem. this is why I am thinking that it is a jetting issue, especially since the rear carb is smaller than the front?
  4. hotroadking

    hotroadking Super Moderator Staff Member

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    could be an intake leak allowing more air in, check the mounts...
  5. FLHTbiker

    FLHTbiker Moderator Staff Member

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    That would be the first place to start
  6. JohnnyBiker

    JohnnyBiker Well-Known Member

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    I am going to have to do that tomorrow as Hot Rider and I get out bikes back tomorrow. We didn't get all of that done to her bike just yet as the uncertainty with my work situation is still unclear.
  7. JohnnyBiker

    JohnnyBiker Well-Known Member

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    So am I to spray the wd-40 right where the intake attaches to the head??
  8. hotroadking

    hotroadking Super Moderator Staff Member

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    Yes. Do u have propane torch?

    Use it unlit open let gas around intake less mess


    Sent from my iPhone using Tapatalk
  9. cowboy

    cowboy Moderator Staff Member

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    Yes & at idel , if it goes up in the rpm you have a leak
  10. JohnnyBiker

    JohnnyBiker Well-Known Member

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    I like this idea more than the wd thats for sure. Now I am going to have wait till it stops sleeting out to get the damn bikes!!:gah::gah::witsend::banghead:
  11. cowboy

    cowboy Moderator Staff Member

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    hello sunshine texas style good for riding most of the year :D
  12. HarleysLR

    HarleysLR Active Member

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    I am wondering why one carb is a different size than the other, I'm not familiar with meteric v twins is that a normal thing?
  13. FLHTbiker

    FLHTbiker Moderator Staff Member

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    The metric bikes I rode the jet sizes were the same. You sure someone didn't screw with it.


    Sent via IPhone
  14. HarleysLR

    HarleysLR Active Member

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    Maybe i miss interpreted what JB said I thought he ment the carbs are different sizes, and yes I think the jetting should be the same, it always was on any other twin or 4 cyclinder that had more than one carb,
  15. FLHTbiker

    FLHTbiker Moderator Staff Member

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    You may be correct as going back and re-reading it JB did say different size carbs but he was saying different size jets to, OK, I'm confused now to
  16. HarleysLR

    HarleysLR Active Member

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    he better show up and straighten us both out, JB where are you? :gah:
  17. chucktx

    chucktx Moderator Staff Member

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    checkin the boots................seems there different also!!!!!!!!!!:D
  18. chucktx

    chucktx Moderator Staff Member

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    check the tech tips section for a full explanation......:rolleyes:
  19. JohnnyBiker

    JohnnyBiker Well-Known Member

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    I did say different carb sizes, but after doing a little better research, I found that the carbs are different. The rear carb is a Mikuni BS36 and the front is a Mikuni bds36. I am trying to find out what the differences are between the two. I knew that they were different and just assumed that the rear one was smaller. Why, I am not sure, but they are different.

    As far as the jet sizes go, I was asking if in fact that the rear carb is jetted the same if I could jet that one differently since that is the carb that I am getting all of the popping out of? Does that help??? :gah::banghead::D
  20. JohnnyBiker

    JohnnyBiker Well-Known Member

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    I think I am going to keep that wiring harness.......:rant::rant::roflmao:

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