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  1. #51
    1131 Adam E.'s Avatar
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    Quote Originally Posted by OsideBill View Post
    the gp 1200 carbs are adjustable as is, besides the chokes had the same linkage piece as the carbs.

    loosen the two allen caps on #2 and #3 and reach inside and move the throttle plate where you want it.
    Thanks Bill. I wasn't sure if the other linkage was different since I have never seen it.

    Thanks Again.


  2. #52
    Moderator OsideBill's Avatar
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    Pics, I hope they explain it better

    Stock Carbs

    back out idle adjuster so that #1 plate is fully closed

    Loosen linkage on carb #2 and #3
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  3. #53
    Moderator OsideBill's Avatar
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    pull some tension on adjuster to take up slack

    while holding slight tension push #2 throttle plate down so it closes completely

    Tighten screws

    repeat process for #3

    The idea is to have them all open in sync, they have built in stops that limit their full open position.

    BTW I just went out and did these pics for you, good thing I have a couple sets of these carbs laying around
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

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  4. #54
    1131 Adam E.'s Avatar
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    Bill,

    I am grateful for all the help you have given me since coming to GreenHulk. If I may continue to ask questions from our phone conversation I would like to know more about drilling out the returns and balancing fuel pressure. As you mentioned this was a common issue in the triple 44's. What exactly goes wrong with the returns?

    To do the modification how what size bit do you use to drill them out? Any special procedures? Also how do you then adjust/balance fuel pressure.

    Thanks,

    Adam

  5. #55
    Moderator OsideBill's Avatar
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    Drilling the returns is a simple mod, the idea is that by opening the built in restriction in the pump body and moving the restriction to the return line you will get even pressure in all carbs. This mod balances the fuel pressure in the entire system. The nice thing is you can add a fuel pressure gauge and monitor your pressure. Even pressure will result in all N&S flowing the same rate at all times. Other benefits are If a pump fails from a creased check valve or for any other reason, the other pumps pick up the slack and maintain fuel to that carb. I believe that this mod will help increase check valve life by actually reducing the pressure they see.

    To do this mod you simply drill out the small restictor hole with an 1/8" drill bit until it breaks through in to the cavity for the return fitting. Then add a hose coupler or tee in the return line with the downstream side tapped to 5mm and a Mikuni main jet screwed in. With the use of a tee I run the branch side to my fuel pressure gauge so that I can set-up proper then monitor fuel pressure. The desired pressure is 1-2 PSI at idle and 5-7 PSI WOT. the tricky part is getting the right jet size to achieve the desired pressure, this is where the fuel pressure gauge comes in handy. You can use one to tune then remove it if you do not want to mount one. I run a long hose then run it up and hold in my lap for tuning.

    This is not a new mod by any means some of the older 1100 carbs that run the remote fuel pump, had a built in restrictor in the last nipple on the return to tank line.
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  6. #56
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    Quote Originally Posted by OsideBill View Post
    Jme I disagree Glass bead works great as long as you take the time to prep and mask like any other job. You get out what you put into it.
    I have some carbs that the paint is flaking off. I would like to glass bead them but before I do. What would be the proper procedure? i.e masking what parts and what should or shouldn't be blasted and then proper cleanup after.

  7. #57
    I'd rather be jet skiing Saltwater n Premix's Avatar
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    Quote Originally Posted by OsideBill View Post
    I think I am sticking with the R&D F/A I got it from Njjer I think can't remember exactly. It is a pain to align the F/A and get the top on though.
    Yea but it looks fricken sick!

  8. #58
    I know this is an old thread but give it go, did you glass your Carbs?

  9. #59

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    To do this mod you simply drill out the small restictor hole with an 1/8" drill bit until it breaks through in to the cavity for the return fitting. Then add a hose coupler or tee in the return line with the downstream side tapped to 5mm and a Mikuni main jet screwed in. With the use of a tee I run the branch side to my fuel pressure gauge so that I can set-up proper then monitor fuel pressure. The desired pressure is 1-2 PSI at idle and 5-7 PSI WOT. the tricky part is getting the right jet size to achieve the desired pressure, this is where the fuel pressure gauge comes in handy. You can use one to tune then remove it if you do not want to mount one. I run a long hose then run it up and hold in my lap for tuning.

    This is not a new mod by any means some of the older 1100 carbs that run the remote fuel pump, had a built in restrictor in the last nipple on the return to tank line.[/QUOTE]

    Do i need to add any Y hose joiner or add extra hose to link the carbs together on my 1200 xlt 2001 or just drill carbs, install jet and re-use existing fuel line?

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