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  1. #1
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    Angry fuel quality and RPM's

    is it possible to lose 180 rpm's because you changed the type of fuel you put in your ski?


    this is exactly what happened to me with my 1300 conversion ski. I swapped to mobil premium (95) on the weekend to do some testing, filled up 50 ltrs mixed it 32:1 with yamasludge and took it out to tune the carbs and do more dialing in. The weekend end before i used BP Ultimate and it pulled 7220 cold and 7190-7200 heat soaked.

    running mobil 95 i lost 180 rpm's from the week before and the only thing added to the ski in that time was outwears to the carbs air filters...sure ok so they can rob a few rpm but not 180 surely....i also did the dual fuel pickup..but that should not affect anything.

    has any one experienced this level of rpm loss from adding outwears or changing fuel ( or a combination of both) ??????


  2. #2
    Mik72e's Avatar
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    Guys been helping Steve with his ski but its doing my head in as much as his.

    With the minor changes he made and to loose 180rpms and not touching the carbs or engine or hull set up is mind blowing i understand every day is different but 180 rpms what else can it be.

    I thought it my be is R&D CDI box is there much different at WOT with a Stock CDI over the 94 curve.

  3. #3
    THE PLATE MAN JIM'S PERFORMANCE's Avatar
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    Get rid of the outwears that will eat up RPM's.

  4. #4
    Mik72e's Avatar
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    Will do Jim
    TY

  5. #5
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    i did not think they would starve the air off that badly but hey lets find out.

    thanks jim.

  6. #6
    They do... they are terrible... I saw a 150 rpm difference on a stage 3 RXT in grand cayman..150 rpm+ when they were removed...

  7. #7
    JetSkiDaddy's Avatar
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    WOW ! Thats good to know. Back in the old XPL 951 days outerwears costed ya 50 rpms. I guess it shows more on these newer, bigger bader beast of today.

  8. #8
    Put your jogging shorts on and go do a mile. Now put a sock in your mouth and do another mile

  9. #9
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    well i pulled the outwears off today and took the bucket out as well and well what do you know, [email protected]

    i went to prop up and stripped two ride plate bolts inserts so my day of testing ended early after 2 runs only

    so there you have it, outwears/socks do indeed rob you of serious rpm's

  10. #10
    Mik72e's Avatar
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    Getting close get them insert in get back out on the water.

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