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  1. #1
    red rider's Avatar
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    Heat fade and elevation question

    I was at Lake Mead this weekend and noticed my rpm's were down to 7800. the outside temp was 104 to 106 and I believe the elevation is anywhere between 1000 and 1500. Does this sound right? the ski still pulled hard just want to make sure. I did have 2 month old gas in as well.


  2. #2
    red rider's Avatar
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    forgot to mention this is an 05 RXP.

  3. #3
    Site Admin Green Hulk's Avatar
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    That's perfectly normal for your RPM's to drop in that kind of heat. The elevation doesn't help either.

    One way to combat heat fade is to go with the Riva or Rotax Racing thermostat.

  4. #4
    West Texas RXP skoepp's Avatar
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    i love this thread, what do you want to know about elevation horsepower affect. Unfortunately i can tell you alot.

    I just figured lake meads density altitude using todays altimer, and pressure, and your temp of 105 and 1500 ft.

    You would be at a density altitude of 5,086 ft.
    Big time decrease in rpm.
    I can take the same setup on ski and run 300 - 350 rpm difference going from 5,600 ft RAD to 2,000 ft RAD.

    It is big time difference.

    I would say at 500 ft elevation or 1,000 to 1,500 RAD your ski would be right at 8,100 rpm.
    Last edited by skoepp; 08-12-2008 at 09:20 PM.

  5. #5
    red rider's Avatar
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    thanks guys. I figured as much. I will be spending money shortly in the store!

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