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  1. #1

    2001 GP1200R engine build questions

    Hey guys,

    Ive been pouring over the site for the answers to a few questions, and it tends to raise more!! haha Hope none of these are too stupid.. I Bought a 01 GP1200R #1 and #2 cylinder didnt have but 50 psi comp. So a rebuild was on the way. I know I know, why buy a ski that doesnt run, I got 2 of them for $3k, and the other runs great. I thought it was a good deal.

    I have the motor back together and set in. While having it apart I have all new gaskets, converted to premix, have a D plate, Installed a ADA head (41 CC) . Have flame arrestors on the way, primer kit on the way, and got a deal on a RIVA ECU that is on the way too.

    With that overview, here are some questions- so I dont screw anything up.

    when installing the carbs does there need to be antype of sealant between the carbs plate/ metal gasket/ reed cage? I dont remeber any being there when I took it apart, just want to make sure.

    Installing the primer kit, does the accelerator pumps go away, or can you leave them on, I seen a number of posts on this, but wasnt clear to me. Is there a good set of instructions somewhere.

    With my mods that are planned, any should I rejet the carbs? Ive been told by somepeople to get it together, run it hard after break in, and pull plugs to see if its running lean then rejet if needed. But I dont want to take a chance on seizing the engine.

    Im installing the power valves, and on the center clinder the linkage (rod) is tough to move by hand. If I turn it using the servo motor linkage its easier, but seperatley, its not as easy as the others. Is there a certain way the bushings are installed could I have them backwards. I did put some grease on them before install.

    I know im not using all the right terms to describe this but hopefully yall know what im talking about. any help would be greatly appreciated.

    Thanks!!


  2. #2

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    Quote Originally Posted by dustin1145 View Post
    Hey guys,

    Ive been pouring over the site for the answers to a few questions, and it tends to raise more!! haha Hope none of these are too stupid.. I Bought a 01 GP1200R #1 and #2 cylinder didnt have but 50 psi comp. So a rebuild was on the way. I know I know, why buy a ski that doesnt run, I got 2 of them for $3k, and the other runs great. I thought it was a good deal.

    I have the motor back together and set in. While having it apart I have all new gaskets, converted to premix, have a D plate, Installed a ADA head (41 CC) . Have flame arrestors on the way, primer kit on the way, and got a deal on a RIVA ECU that is on the way too.

    With that overview, here are some questions- so I dont screw anything up.

    when installing the carbs does there need to be antype of sealant between the carbs plate/ metal gasket/ reed cage? I dont remeber any being there when I took it apart, just want to make sure.

    Installing the primer kit, does the accelerator pumps go away, or can you leave them on, I seen a number of posts on this, but wasnt clear to me. Is there a good set of instructions somewhere.

    With my mods that are planned, any should I rejet the carbs? Ive been told by somepeople to get it together, run it hard after break in, and pull plugs to see if its running lean then rejet if needed. But I dont want to take a chance on seizing the engine.

    Im installing the power valves, and on the center clinder the linkage (rod) is tough to move by hand. If I turn it using the servo motor linkage its easier, but seperatley, its not as easy as the others. Is there a certain way the bushings are installed could I have them backwards. I did put some grease on them before install.

    I know im not using all the right terms to describe this but hopefully yall know what im talking about. any help would be greatly appreciated.

    Thanks!!

    Dude, sorry no one has welcomed you to the forum..... welcome

    You basicly have a "Stage II" set up for a GPR 1200.

    If you go with aftermarket flame arrestors, then you have a lower "signal" or suction pressure. You will have more volume of air flow, but less suction pressure. You should rejet.

    Standard jetting would be 110 pilots, 120 mains, 1.5 Needle and seat, with 95 gram springs. Your pop off pressure should be about 41-43 psig.... it is most important that they all "pop off" at fairly close pressures. T-handles for low and high speed are a must starting with all screws turned out about 2 turns each. You will probably wind up 1 turn out on the high adjustment and 7/8 on the lows as you adjust them in for best performance. This is STANDARD STUFF for your boat, and YOUR BOAT MAY VARY..... ie it is a good place to start.

    Some people put the gaskets in dry. I put a small amount of grease on them so that they will not tear up when I remove them. The most important thing is to make sure that the carb bank is torqued on properly. Many an engine has been lost here due to air leaks.

    These carburetors have a weak signal and therefore have a lean spot at 3/4 throttle. The accellerator pump helps to deal with the lean spot. With your new jetting however, that spot is minimized and you therefore need to remove the pump if you use new jetting. If you leave the pump in, then you will run way rich. I personally removed the linkage, but left the primer bulb. I use that instead of an aftermarket priming system. Actually a friend named Fercho showed me how to do it way back when.

    Cannot comment on the linkage because I use gas valves. I would suspect that they all should open freely and that you should look #2 over again.

    Do not run it hard until you are certain that it is running rich (fat). At two turns out on all of your jets, you should be OK, but in a break in, slow is good. Do a search on Carb jetting with an eye on "stage II" type GPR's and educate yourself. There are lots of different ways to mess up carbs, and remember that you have 3x the fun.

    In the immortal words of George Grabowski "You think that education is expensive, try ignorance!"

    Good luck!

  3. #3

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    good tips and good to see someone take the time to give advice

  4. #4
    All hail the Chief! fullboogie's Avatar
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    Can't really add anything to Salty's response other than get a good tach to do proper tuning.

    And I would personally use a lot of 1211 to seal the reed plate to the case. Lots and lots of leaks occur right there, and a new gasket/proper bolt torque does not guarantee no leaks. Been there and done that many times. And so you know, an air leak right there can cause disaster. Best bet is to pressure test the engine after rebuild and before installation.

  5. #5
    Thanks for all the info, im going to do some more research on jetting like you said, thanks for putting me in the right direction. Im sure that ill have a bunch more questions. If you have any more tips/tricks, id be glad to hear'em.

    Again, thanks for the info everyone.

  6. #6
    Moderator beerdart's Avatar
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    Welcome to the Hulk..

    Lots of good info in the How to section..

    Anymore questions just ask..

  7. #7

    ada head cooling lines

    Can u post pics. of your cooling lines setup on your ADA Head?

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