Page 1 of 4 1 2 3 ... LastLast
Results 1 to 10 of 32
  1. #1

    Exclamation Danger!! '06rxp high speed instability!

    Hi guys, this is my first post, but I feel it is very important to share my experience for all your benefits, and to get your feedback about the problem.

    First some background-
    A while back, I cracked my intake grate mounting holes in the pump shoe while flipping my ski right side up. I was simply following the user's manual to grip the intake grate and pull it while pushing on a sponson with your foot. Anyways, my intake grate ripped off shortly after riding back home.

    I then checked the forum, and heard a lot of you guys have been riding without intake grates without serious effects- some people say their ski runs better without one, some with. So.. I thought it was safe to keep running my ski without the grate. My ski was a full stage 1 at that point, and I was having no problems whatsoever without the intake grate- hitting 70-71mph at 8050rpms and stable.

    Now the danger-
    Later, I installed the fizzle i\c, 42lb injectors, solas 15/20, and a supercharger wheel making 11lbs boost at 8200rpm. While installing all this, I noticed the leading edge of the pump shoe / support was missing some material- jagged, irregular. Since I had no problems up to that point, I thought I was ok.

    Wrong! While testing the new parts, I got the ski up to 7800 rpm (definitely feeling faster with the 15\20 at this point) and it continued pulling until....WHAMMO!! The nose of the ski dives down a few inches, pulls hard to one side, and I proceed to fly off then bounce along the water at over 70mph! Chipped a couple of teeth, coughing blood, seeing stars, winded, I think to myself- What the hell just happened!!?? The water was perfectly flat! Never heard of this before. Luckily a friend was spotting me from a boat to make sure I was ok.

    Well I was understandably cautious riding after that, but soon enough.. I wanted to see what the new parts would do- so I pushed it to w.o.t. on calm water again. Who knows- maybe that first dive was a fluke? Sure enough, it happened again!! Same dive and pull- but I was more prepared for it this time, and let off the throttle a bit before it bucked me off that time. I still think I broke a bone in my foot off the edge of the ski that time...


    Well there you have it. My theory is that the ragged edge of the pump shoe running at such a high speed (72+mph) without an intake grate is creating some kind of turbulence/cavitation wave directly under the front of the ski. When the speed and resulting turbulence crosses a point- the buoyancy of the water under the ski is less, and the ski then dives into the bubbles. Then the ski catches "hard" water again, but just wants to go off in a certain direction. This all happens so fast, it literally 'bucks' you at top speed, so your own hands change the direction of the handlebars- and then it all over- goodbye...

    So what do you all think?? Has anybody had anything close to this happen to them at high speeds over flat water? With a damaged intake grate / pump shoe? With a perfect grate / shoe setup? Does my thoery make sense to anyone?

    Just wanted to warn people, and hear what you thought about it.

    Cheers,
    Adam


  2. #2
    Nothin' better than Doo'in it! BigDaddyRXP's Avatar
    Join Date
    Aug 2007
    Location
    Tampa Bay, FL
    Posts
    9,202
    +1
    673
    Are fuckin kidding me? Where have you ever read about people not running an intake grate? I can't believe you made it to 71 mph without being bucked off... missing an intake grate, and having a damaged pump shoe

    You need to replace your pump shoe, and intake grate before you ride that ski again!!!!!!!!

    Btw... welcome to the forum!

  3. #3
    Eric Ocman's Avatar
    Join Date
    Aug 2008
    Location
    Cataula, Georgia, United States
    Posts
    4,700
    +1
    77
    Quote Originally Posted by Zap View Post
    Hi guys, this is my first post, but I feel it is very important to share my experience for all your benefits, and to get your feedback about the problem.

    First some background-
    A while back, I cracked my intake grate mounting holes in the pump shoe while flipping my ski right side up. I was simply following the user's manual to grip the intake grate and pull it while pushing on a sponson with your foot. Anyways, my intake grate ripped off shortly after riding back home.

    I then checked the forum, and heard a lot of you guys have been riding without intake grates without serious effects- some people say their ski runs better without one, some with. So.. I thought it was safe to keep running my ski without the grate. My ski was a full stage 1 at that point, and I was having no problems whatsoever without the intake grate- hitting 70-71mph at 8050rpms and stable.

    Now the danger-
    Later, I installed the fizzle i\c, 42lb injectors, solas 15/20, and a supercharger wheel making 11lbs boost at 8200rpm. While installing all this, I noticed the leading edge of the pump shoe / support was missing some material- jagged, irregular. Since I had no problems up to that point, I thought I was ok.

    Wrong! While testing the new parts, I got the ski up to 7800 rpm (definitely feeling faster with the 15\20 at this point) and it continued pulling until....WHAMMO!! The nose of the ski dives down a few inches, pulls hard to one side, and I proceed to fly off then bounce along the water at over 70mph! Chipped a couple of teeth, coughing blood, seeing stars, winded, I think to myself- What the hell just happened!!?? The water was perfectly flat! Never heard of this before. Luckily a friend was spotting me from a boat to make sure I was ok.

    Well I was understandably cautious riding after that, but soon enough.. I wanted to see what the new parts would do- so I pushed it to w.o.t. on calm water again. Who knows- maybe that first dive was a fluke? Sure enough, it happened again!! Same dive and pull- but I was more prepared for it this time, and let off the throttle a bit before it bucked me off that time. I still think I broke a bone in my foot off the edge of the ski that time...


    Well there you have it. My theory is that the ragged edge of the pump shoe running at such a high speed (72+mph) without an intake grate is creating some kind of turbulence/cavitation wave directly under the front of the ski. When the speed and resulting turbulence crosses a point- the buoyancy of the water under the ski is less, and the ski then dives into the bubbles. Then the ski catches "hard" water again, but just wants to go off in a certain direction. This all happens so fast, it literally 'bucks' you at top speed, so your own hands change the direction of the handlebars- and then it all over- goodbye...

    So what do you all think?? Has anybody had anything close to this happen to them at high speeds over flat water? With a damaged intake grate / pump shoe? With a perfect grate / shoe setup? Does my thoery make sense to anyone?

    Just wanted to warn people, and hear what you thought about it.

    Cheers,
    Adam
    I dont think you will find a post here mentioning running WITHOUT and intake grate bro.

    You need to put one on asap before you get thrown off again.

  4. #4
    Michigan sn-95's Avatar
    Join Date
    Sep 2010
    Location
    Hamilton MI
    Posts
    734
    +1
    32
    Quote Originally Posted by Zap View Post
    Hi guys, this is my first post, but I feel it is very important to share my experience for all your benefits, and to get your feedback about the problem.

    First some background-
    A while back, I cracked my intake grate mounting holes in the pump shoe while flipping my ski right side up. I was simply following the user's manual to grip the intake grate and pull it while pushing on a sponson with your foot. Anyways, my intake grate ripped off shortly after riding back home.

    I then checked the forum, and heard a lot of you guys have been riding without intake grates without serious effects- some people say their ski runs better without one, some with. So.. I thought it was safe to keep running my ski without the grate. My ski was a full stage 1 at that point, and I was having no problems whatsoever without the intake grate- hitting 70-71mph at 8050rpms and stable.

    Now the danger-
    Later, I installed the fizzle i\c, 42lb injectors, solas 15/20, and a supercharger wheel making 11lbs boost at 8200rpm. While installing all this, I noticed the leading edge of the pump shoe / support was missing some material- jagged, irregular. Since I had no problems up to that point, I thought I was ok.

    Wrong! While testing the new parts, I got the ski up to 7800 rpm (definitely feeling faster with the 15\20 at this point) and it continued pulling until....WHAMMO!! The nose of the ski dives down a few inches, pulls hard to one side, and I proceed to fly off then bounce along the water at over 70mph! Chipped a couple of teeth, coughing blood, seeing stars, winded, I think to myself- What the hell just happened!!?? The water was perfectly flat! Never heard of this before. Luckily a friend was spotting me from a boat to make sure I was ok.

    Well I was understandably cautious riding after that, but soon enough.. I wanted to see what the new parts would do- so I pushed it to w.o.t. on calm water again. Who knows- maybe that first dive was a fluke? Sure enough, it happened again!! Same dive and pull- but I was more prepared for it this time, and let off the throttle a bit before it bucked me off that time. I still think I broke a bone in my foot off the edge of the ski that time...


    Well there you have it. My theory is that the ragged edge of the pump shoe running at such a high speed (72+mph) without an intake grate is creating some kind of turbulence/cavitation wave directly under the front of the ski. When the speed and resulting turbulence crosses a point- the buoyancy of the water under the ski is less, and the ski then dives into the bubbles. Then the ski catches "hard" water again, but just wants to go off in a certain direction. This all happens so fast, it literally 'bucks' you at top speed, so your own hands change the direction of the handlebars- and then it all over- goodbye...

    So what do you all think?? Has anybody had anything close to this happen to them at high speeds over flat water? With a damaged intake grate / pump shoe? With a perfect grate / shoe setup? Does my thoery make sense to anyone?

    Just wanted to warn people, and hear what you thought about it.

    Cheers,
    Adam

    dude.

  5. #5
    MSRXP's Avatar
    Join Date
    Sep 2010
    Location
    Central MS
    Posts
    5,448
    +1
    7
    Quote Originally Posted by Zap View Post
    Hi guys, this is my first post, but I feel it is very important to share my experience for all your benefits, and to get your feedback about the problem.

    First some background-
    A while back, I cracked my intake grate mounting holes in the pump shoe while flipping my ski right side up. I was simply following the user's manual to grip the intake grate and pull it while pushing on a sponson with your foot. Anyways, my intake grate ripped off shortly after riding back home.

    I then checked the forum, and heard a lot of you guys have been riding without intake grates without serious effects- some people say their ski runs better without one, some with. So.. I thought it was safe to keep running my ski without the grate. My ski was a full stage 1 at that point, and I was having no problems whatsoever without the intake grate- hitting 70-71mph at 8050rpms and stable.

    Now the danger-
    Later, I installed the fizzle i\c, 42lb injectors, solas 15/20, and a supercharger wheel making 11lbs boost at 8200rpm. While installing all this, I noticed the leading edge of the pump shoe / support was missing some material- jagged, irregular. Since I had no problems up to that point, I thought I was ok.

    Wrong! While testing the new parts, I got the ski up to 7800 rpm (definitely feeling faster with the 15\20 at this point) and it continued pulling until....WHAMMO!! The nose of the ski dives down a few inches, pulls hard to one side, and I proceed to fly off then bounce along the water at over 70mph! Chipped a couple of teeth, coughing blood, seeing stars, winded, I think to myself- What the hell just happened!!?? The water was perfectly flat! Never heard of this before. Luckily a friend was spotting me from a boat to make sure I was ok.

    Well I was understandably cautious riding after that, but soon enough.. I wanted to see what the new parts would do- so I pushed it to w.o.t. on calm water again. Who knows- maybe that first dive was a fluke? Sure enough, it happened again!! Same dive and pull- but I was more prepared for it this time, and let off the throttle a bit before it bucked me off that time. I still think I broke a bone in my foot off the edge of the ski that time...


    Well there you have it. My theory is that the ragged edge of the pump shoe running at such a high speed (72+mph) without an intake grate is creating some kind of turbulence/cavitation wave directly under the front of the ski. When the speed and resulting turbulence crosses a point- the buoyancy of the water under the ski is less, and the ski then dives into the bubbles. Then the ski catches "hard" water again, but just wants to go off in a certain direction. This all happens so fast, it literally 'bucks' you at top speed, so your own hands change the direction of the handlebars- and then it all over- goodbye...

    So what do you all think?? Has anybody had anything close to this happen to them at high speeds over flat water? With a damaged intake grate / pump shoe? With a perfect grate / shoe setup? Does my thoery make sense to anyone?

    Just wanted to warn people, and hear what you thought about it.

    Cheers,
    Adam
    Wait... Seriously... No grate, really? Get a top loader and a life insurance policy. Both may come in handy if you pull that again. Replace that pump shoe as well.

    Oh yeah, almost forgot... Welcome to the forum.....

  6. #6
    Swedish Viking Craigo's Avatar
    Join Date
    Jun 2008
    Location
    Seattle
    Posts
    1,367
    +1
    62
    I think you read posts about riding with or without the IMPELLER BOOT/NOSECONE.

    Quote Originally Posted by Zap View Post
    I then checked the forum, and heard a lot of you guys have been riding without intake grates without serious effects- some people say their ski runs better without one, some with.
    Sorry to hear that you hurt yourself.

    Welcome to the forum!

  7. #7
    formerly Gold06RXP Turbo Nick's Avatar
    Join Date
    May 2007
    Location
    Dayton, OH
    Posts
    2,095
    +1
    97
    I thought ive heard it all WOW!!!!!!

  8. #8
    ou812's Avatar
    Join Date
    Jun 2006
    Location
    Riverside,ca
    Posts
    6,210
    +1
    198
    +1 Craigo,
    Intake grates:
    The hulls that are able to run without the intake grate are the X4 hulls, or better known as the 1995-1996 xp, '97 and up spx's. He just got confused on which seadoo hull it was is all i'm sure.
    Don't be so harsh on the guy, it's his 1st post and now he's gun shy..

  9. #9
    Sturm215's Avatar
    Join Date
    May 2010
    Location
    Lakeland florida
    Posts
    1,893
    +1
    64
    Glad your okay!You definatly have bigger Kahunas then I do to even try it twice !!

  10. #10
    KC Blue Thunder's Avatar
    Join Date
    Oct 2007
    Location
    Jacksonville, Florida
    Posts
    2,079
    A couple of things come to mind..... First off welcome to the forum you will find any and all help needed in relation to your ski. Second .... I'm glad that you are ok and that the injuries arent that bad. Third... and with all due respect... "You are a bonehead sir" I've been a member of this forum for well over 4 years and I've yet seen a tread saying that its ok to ride without the grate specially on modified ski's. If you find the tread in which you read this please post a link so that someone can correct this information. You my friend are very fortunate to not have had a worst spill that could have caused you permanent damage. Safety should be your first concern the fun second. Good luck in the future and please update your insurance policy if you decide to continue riding recklessly. [/SIZE][/SIZE][/SIZE] [FONT="Comic Sans MS"][/FONT] Not trying to dog you out or make fun of the situation but this is the type of practice that kills peeps out there, take care of yourself bud.

Page 1 of 4 1 2 3 ... LastLast

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. PWC High Speed testing!
    By 2fast4u in forum Yamaha PWC Performance (2-stroke)
    Replies: 79
    Last Post: 05-08-2009, 08:29 AM
  2. Safety considerations on high speed runs
    By way2fast in forum Open Discussion
    Replies: 1
    Last Post: 12-17-2007, 10:16 AM
  3. 98 polaris slth Keihin cdk II carbs, no high speed needle, wtf?
    By bigjump300 in forum Polaris How To & FAQs
    Replies: 13
    Last Post: 03-28-2007, 11:25 AM
  4. Hook-Up in Ocean (High Speed)
    By RXP PIT BOSS in forum 4-Tec Performance
    Replies: 4
    Last Post: 09-10-2006, 12:20 PM
  5. High speed adjustment difficulty
    By OCFZR in forum Yamaha PWC Performance (2-stroke)
    Replies: 7
    Last Post: 06-27-2006, 07:38 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •