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  1. #1

    XLT needs some bottom end

    I just took my 99 xl1200ltd out for the first time. Bought it blown up and rebuild just about everything in it. All stock except for D-plate & chip, R&D intake & plate, solas 13/19 and jetworks mod. I did test the jetworks and set it to open around 3500 (only used on board tac, will fine tune later with after market). Ran well, but it wouldn't pull out the hole worth a crap. My buddy had his wave venture 1100 and he was killing with the hole shot, and would run dead even with up top. Does this sound normal? Am I over propped? On board tac only read about 6200 on top but I know it isn't very accurate. Any suggestions where to start looking?

  2. #2

    Join Date
    Jan 2006
    Texas City, Texas
    I thought that the XLT's ran with a 12/18, not a 13/19.

    What have you done with your intake and ride plate.?

  3. #3
    philip_gpr's Avatar
    Join Date
    Dec 2005
    I'd suggest you get an external tach to get an exact reading

    the OEM tach is accurate - it is just hard to read

    yes a 12/18 is the correct prop for a stock motor, so that is reducing your rpms by 100 or so

    if the RPMs are in fact 6200 then that is telling you there is a problem with the motor

  4. #4
    something seems wrong, i have a 99 xl1200 with the r&d intake grate, jim cut plate, free flow exhaust, filled in the pump shoe, d plate, and a solas 12/18 prop. i was turning 7300 rpm in 75 degree weather and in 90 degree wether i was turning around 7170 on a TINY TACH. i put on a group k head with the 12/18 and it put me at 7250 rpm in 90 degree weather and very humid. then i changed to a 13/19 solas prop and it woke the ski up, but now i am only turning around 7200 in hot weather (IN TENNESSEE). gps on cooler days with me (390lbs.) on it is around 64.8 on warmer days is 63.5 with half take of gas.

  5. #5
    I didn't have much time today to look at it, but I quickly found that the powervalves weren't moving (I have wave eater clips and couplers). Took the servo out and the screw had come out of the shaft so the cam wasn't moving. I'm sure that was a big part of the problem.

  6. #6
    XL800's Avatar
    Join Date
    Nov 2006
    Ellerslie GA
    yes at 6000 your power valves open, with out that you dont have much power!

  7. #7
    how many rpm's are you turning now?

  8. #8
    Like a chimp with a ball-peen hammer smackwave's Avatar
    Join Date
    Dec 2005
    Annapolis, MD
    If the screw was out of the servo wheel most likely the pressure from the exhaust pushed the valves open - which explains the horrible holeshot. It probably felt like you were dragging an anchor until the RPM hit about 5500 and the engine got on the pipe. You're definitely a bit slow on top, though. With the Riva plate you should be a few MPH faster than a 'Venture 1100.

    Milling your head or getting a set of aftermarket heads should allow you to spin that 13/19 no problem. Stock compression you might be a bit overpropped, but not outrageously so. With your mods and stock compression you should still be at or above 7000 RPM.

    I know you've just rebuilt it, but have you done a compression check with valves open and closed just to be sure?

  9. #9
    I'm out of town and will be for 2 weeks so I can't work on it. I tested compression after I assembled the engine a couple of months ago. I have it written down at home but they were all within 4lbs of 120. I didn't do anything to the R&D plate or grate other than line them up when I bolted them on. I did put in a pump seal kit and I sealed the pump shoe when I put it in. When I get back I will use a tach to get some good numbers after I fix the powervalve controller.

    Who can mill the head and has good turn around time?

  10. #10
    Yellow93's Avatar
    Join Date
    Apr 2006
    San Antonio, Texas, United States
    I've heard good things about GroupK and Jim...

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