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  1. #1

    Join Date
    Oct 2007
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    VA Beach
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    problem with accleration and top end. 1200

    Hello,

    This is my first summer in the sport. I snagged a 00 GPR with 25 hrs. on it from a family member. Now it has 87 hrs. and I was running full throttle last Sunday and I just dropped to 3/4 power and I couldn't get it above 4000 rpm

    Compression is 120 in each cylinder. I rebuilt the carbs, put some stuffers in the Reeds while I was down there, started running high test and replaced the plugs. I notice a brass fitting on the #1 carb cover was broken. Replace that..... Still having issues.

    She wants to bogged down at low end, decent acceleration at midrange but top-end is off 15 mph and can only muster 6000 rpm.

    I've notice that she smokes more now that she did before. Please if you could steer me in the next trouble shooting step I'd really be thank full.
    Last edited by HOPGPR00; 10-27-2007 at 04:33 PM.


  2. #2
    Moderator beerdart's Avatar
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    Welcome to the hulk. Does the impeller and crankshaft spin buy hand with the plugs removed? Is the CAT still installed?

  3. #3
    My son (mohawk man) jeffsntx's Avatar
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    Sep 2006
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    Belton TX
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    My guess would be that the cat con failed and is "plugging" the pipe, or the power valves are not opening.

  4. #4

    Join Date
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    Welcome to the forum.

    Catalytic Converter. Pull the pipe (Stinger) and inspect. If you find that it is missing or broken, pull the water box and inspect for parts (shake it).

    This would be my guess.

  5. #5

    Join Date
    Oct 2007
    Location
    VA Beach
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    CAT Removed

    Thanks for the quick response. I'm sorry I should have said what I've done to her so far.

    Install D plate, remove water box and installed straight pipe.
    Reed Stuffers
    Ride plate
    Impeller
    intake grate
    pump seal kit

    I really haven't done much to the engine, and this issue worries me. When I had her opened up, I saw nothing out of the ordinary, (well with what I know so far).

    What should I look for if the Cat is already remove and the Impeller doesn't free spin with the plugs out??

    Thanks

  6. #6
    Moderator beerdart's Avatar
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    Check for a droped power valve.

  7. #7

    Join Date
    Oct 2007
    Location
    VA Beach
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    25

    Power Valve

    How do I check for a dropped power valve?

    Thank you

  8. #8
    Moderator beerdart's Avatar
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    Remove the covers on the valves and look for the pin that hold the valve to the shaft.

  9. #9
    305coco's Avatar
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    im no expert, but i would suggest you pull each individual power valve and make sure is in 1 piece, on my bro's ski a valve broke in half and if you just pull the covers and this is your first time doing this you wont notice that the valve is broken unless you try pulling it out and only the lil shaft comes out

  10. #10
    WE DONT DIAL 911 RDH's Avatar
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    you got two choices for solving the valve problem without switching to 05& up cylinders or welding them in place...you could get the waveeater clips to keep the pin from sliding and allowing the valve to drop, thats the cheapest solution, or go with gas valves, a little pricey but worth not having servos, cdi settings etc..

    one of these are a must to have imo just like pump tunnel reinf/updated inserts

    waveater= 100$
    gas valves =600$
    Last edited by RDH; 10-27-2007 at 11:42 PM.

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