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  1. #1
    Michigan sn-95's Avatar
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    Cause of RPM gain?

    O.K., So I decided to try running my 3" Kanaflex "without" my filter. Took it to the lake and, whamo! 80-100 RPM gain. Now "as luck would have it" comes the monkey wrench. The day I tested it with the filter was about 20 degrees warmer than it was yesterday when I tested without the filter.
    So..was my gain because of the weather, or running filter free?

    BTW ,is it normal to lose abot 50 RPM once everything is hot?


  2. #2
    Laxcrazy23's Avatar
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    I bet a lot of people are going to chime in, but Air temp, humidity, and the fact that there is that much less restriction of air going to the motor will give you that little increase. ive had gains of 160-180 when the air is cooler.

  3. #3
    Eric Ocman's Avatar
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    95 degree air vs 60 degree air 8980 RPMs vs 8700 almost 300 rpms

  4. #4
    Michigan sn-95's Avatar
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    Wow, I was hoping the air temp wouldn't be that much of a factor. I'll probably just put my filter back on then.

  5. #5
    richrxp's Avatar
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    Quote Originally Posted by sn-95 View Post
    Wow, I was hoping the air temp wouldn't be that much of a factor. I'll probably just put my filter back on then.
    There is no need to put the filter back,many are running without.
    I'm withtout for 2 seasons now and no problems,not even in heavy seas.

  6. #6
    Michigan sn-95's Avatar
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    Quote Originally Posted by richrxp View Post
    There is no need to put the filter back,many are running without.
    I'm withtout for 2 seasons now and no problems,not even in heavy seas.
    I'm paranoid about sucking in water, my thinking is that an Oiled gause filter like I originally set it up with will help keep water out. I've read the articles that tell you not to run one like that, but I have it in a spot that it would be very hard to "soak it" enough where it would collapse, but running filterless I'm sure I could get a few drops sucked into the hose. I may end up leaving it off, not sure yet. Right now I just have a screen clamped over the end of the hose. "It does sound cool like that "

  7. #7
    Eastside Powersports Slow 91's Avatar
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    air temp and humidity is a huge factor. both my skis really come alive at the end of the day when it cools down a bit.

  8. #8
    Mod less, ride more! troyheb's Avatar
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    Humidity plays more into it than air temp. I recently went to Arizona and the air temps where in the 110's, but humidity was very low 20% range or less. My TX was running 8160-8180. Back home with air temp in the high 90's, but with 90%+ humidity I was only see 8020-8040.

  9. #9
    asphalt, dirt, and water are my playgrounds. ViperRy's Avatar
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    +1 on humidity, it's a performance killer. The colder, less humid, and unrestricted the air, the more power you make.

  10. #10
    h2jim's Avatar
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    Yes everyone blames the heat for power loss but it is the hummidity that's the problem. Taking the filter off will gain you 50+ rpms.

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