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Thread: Lost 1 mph.....

  1. #1
    sweetbats's Avatar
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    Lost 1 mph.....

    In October, hit 72.7 on my RXP. Low humidity day.

    Today was out in the cold rain (crazy I know). I could only muster 71.7 today.

    The changes from last time were:

    Higher humidity- 100% today.
    Lower lake temp by 10 degrees. (50 degrees today)
    Lower air temp by 10 degrees. (40 degrees today)
    New NGK spark plugs.
    Reduction nozzle this time with 81 mm ring.

    I ran right at 8100 RPM, so was happy about that with the 81 mm ring.

    Would the humidity cost me 1 mph?

    Thanks in advance!


  2. #2
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    Quote Originally Posted by sweetbats View Post
    In October, hit 72.7 on my RXP. Low humidity day.

    Today was out in the cold rain (crazy I know). I could only muster 71.7 today.

    The changes from last time were:

    Higher humidity- 100% today.
    Lower lake temp by 10 degrees. (50 degrees today)
    Lower air temp by 10 degrees. (40 degrees today)
    New NGK spark plugs.
    Reduction nozzle this time with 82mm ring.

    I ran right at 8100 RPM, so was happy about that with the 82 mm ring.

    Would the humidity cost me 1 mph?

    Thanks in advance!
    The weather cost me 500 RPM's today, so 1 MPH is very possible.

  3. #3
    Site Admin Green Hulk's Avatar
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    Quote Originally Posted by sweetbats View Post
    Would the humidity cost me 1 mph?
    absolutely!

  4. #4
    YoYamma's Avatar
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    Yep, Sea-Doos like dry, cool air the best...

  5. #5
    sleeplessnMS's Avatar
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    Seems I always get my best speeds in 60 degrees 50%humity and water -60degrees. Humidity is a hp killer fo sho....

  6. #6
    SHO stopper palmbeach jesse's Avatar
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    Quote Originally Posted by Alex13 View Post
    The weather cost me 500 RPM's today, so 1 MPH is very possible.
    me too...i lost 300....at least now i know it wasnt just my ski...

  7. #7
    sweetbats's Avatar
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    Lots of people on here tonight! Thanks for all the responses. I was bummed, but given that it was not only high humidity, but 100% humidity, I feel better!

    The good news was some gains on the T-X with limited mods so with cooler, dryer air, I should see even more next time out.

    Thanks guys.

  8. #8
    West Texas RXP skoepp's Avatar
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    Air quality changes your RAD (realitive air density).
    The better the air the more hp you will gain or loose if air is not good.

    I use the attached link to tract air quality from one weekend to the next. It is good to know so you can relate to the performance of your ski.

    This is a good link to use: http://wahiduddin.net/calc/calc_hp_dp.htm

  9. #9
    Dirty Sanchez's Avatar
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    Sorry to hear you lost of speed. But now you know why I didn't want to come down to Anna. I knew it would be good for testing and a painful ride in the rain. Glad to hear your nozzle worked! Hopefully in a week or so we'll get a decent weekend for some riding.

  10. #10
    sweetbats's Avatar
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    Dirty,

    Yep, I knew it was going to be ugly, but wanted to keep the "ski each month" streak alive. Sitting at 16 months right now. January is the really cold one, usually.

    The goggles definitely came in handy. Heard one boat on Lake Anna, but never saw anyone on the water besides me and my buddy.

    Hope to ride with you soon.

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