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  1. #1
    bowsniper's Avatar
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    785 Triple pipe water cooling explanation

    Can someone explain eaxactly whats going on in the triple pipes in relation to the water flow.. where it starts, what happens to it, does it get sprayed in? or just flows by pressure or? the speed of the ski? or engine rpms?

    Does the water flow back n forth thur it or just 1 way? whats the 4 way valve for? does it devolop pressure or is it just way to exit the water all together? do bigger pissers have an effect on performance? like a 1/4 verses a 3/8?

    what about the jetworks valve in or not?. do the exhaust valves work in conjunction with the water and flow pressure?

    I get the idea of how they work with the pressure waves cramming the fuel mixture from the pipe into the cylinder.. but thats on the inside of the pipe. if your rpms are right, it all gets crammed back in the cylinder..
    if not you just loose that part of the charge and loose horse power because of it.

    thats why they are gas hogs.. whether ya use it or not, it goes right thru.lol

    I hear you can shorten the pipes for higher rpms or tighten up the stingers to increase the heat in the pipe. shortened pipes shorten the time it takes for the presuure wave to return to the cylinder.

    so that would mean the water would have less time to cool off also. it goes thru the system faster. although your generating way more heat too in the pipe because of the higher rpms. so things would even out i would think as far as temps go. my pipes are in the lows 100's or high 90's.. not hot at all..

    But the inside flow I dont understand fully. Thanks for any insight..

    Now that im thinking about all this. it is a handful.lol


  2. #2
    I'D RATHER SWEAT THAN SHIVER hyoctane23's Avatar
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    I'll do my best to explain. Someone correct me if I'm wrong!!

    Quote Originally Posted by bowsniper View Post
    Can someone explain eaxactly whats going on in the triple pipes in relation to the water flow.. where it starts, what happens to it, does it get sprayed in? or just flows by pressure or? the speed of the ski? or engine rpms?

    When you first start, some of the water is diverted from the pump to the red manifold due to the water pressure being developed in the jet pump. From there, it is divided between the cylinder cooling jackets and the pipe cooling jackets. Depending on the restrictor size, a different amount of water will flow to each of these systems. Also, depending on what water routing you use, some water is then diverted to the stingers.

    Does the water flow back n forth thur it or just 1 way? whats the 4 way valve for? does it devolop pressure or is it just way to exit the water all together? do bigger pissers have an effect on performance? like a 1/4 verses a 3/8?

    The water only goes one way....in and then out. The 4 way tee (I assume is what you're talking about) divides the water flow for the stingers.

    I would assume a larger pisser wouldn't do anything simply because the restrictor size on the water manifold. You can only flow so much water through that restrictor there so the exit size doesn't have much effect, if any at all.


    what about the jetworks valve in or not?. do the exhaust valves work in conjunction with the water and flow pressure?

    The jetworks valve allows no water to flow into the stingers at idle and low RPM until the water pressure in the pump increases to the "cracking pressure." This allows your waterbox and/or collector to clear out the water that might be in there, thus allowing a better holeshot. That is because you don't have to use the exhaust pressure to clear out all that water.

    The exhaust valves located on the cylinders do not have any effect on the water flow. These are controlled by mechanical or electric means (that is, gas valves vs. CDI controlled valves).


    I get the idea of how they work with the pressure waves cramming the fuel mixture from the pipe into the cylinder.. but thats on the inside of the pipe. if your rpms are right, it all gets crammed back in the cylinder..
    if not you just loose that part of the charge and loose horse power because of it.

    Yes, they work in two ways...first by scavenging the burnt gasses out of the cylinder and drawing fresh fuel mixture into the cylinder....but also into the exhaust pipe. Then the sound wave hits the converging cone portion and stinger and stuffs the gas back into the cyliner right before the piston closes the exhaust port.

    thats why they are gas hogs.. whether ya use it or not, it goes right thru.lol

    Might be due the high RPM motor of the 785.

    I hear you can shorten the pipes for higher rpms or tighten up the stingers to increase the heat in the pipe. shortened pipes shorten the time it takes for the presuure wave to return to the cylinder.

    Shortening the pipe makes the reflecting wave come back sooner. If it comes back sooner, you can operate the motor at a higher RPM.

    Making the stinger smaller works by increasing the returing wave intensity I believe. This has the effect of increasing the heat because all the hot exhaust gases aren't able to escape the pipe as quickly....I think??


    so that would mean the water would have less time to cool off also. it goes thru the system faster. although your generating way more heat too in the pipe because of the higher rpms. so things would even out i would think as far as temps go. my pipes are in the lows 100's or high 90's.. not hot at all..

    But the inside flow I dont understand fully. Thanks for any insight..

    Now that im thinking about all this. it is a handful.lol

  3. #3
    bowsniper's Avatar
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    well that clears things up.. thanks.. quit breaking your ski!!!!!! its summer! wait till fall on a cold october day, then break it.lol anyone else have anything to add?

  4. #4
    SPEED KILLS, BUT YOU GET THERE QUICKER Keddano's Avatar
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  5. #5
    bowsniper's Avatar
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    great thread dano. thx.. I believe I have the watcon routing already and the jet works valve.. bot those pipes are whole different subject I see.. it can get complicated. this year had that, he left,someone else did another designm then randys routing.. Randy knows his stuff!

  6. #6
    i know this has been beaten to a pulp, but i just want to make sure i get it right. With the Watcon water routing, the E marked spots in the diagram (water out from stingers) is unrestricted, however, my service manual says these are calibrated orifices and should not be changed. What is the reasoning behind taking them out? Thanks guys.
    Last edited by slx1200; 06-17-2013 at 01:05 PM. Reason: spelling

  7. #7
    I'D RATHER SWEAT THAN SHIVER hyoctane23's Avatar
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    You don't need a restrictor on the outlet E of the pissers because the water is already restricted at the red water manifold at outlet A.

  8. #8
    and since my water manifold is stock on a 1999 this should already be there correct?

  9. #9
    I'D RATHER SWEAT THAN SHIVER hyoctane23's Avatar
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    Double check inside the barbs in the red water manifold. They should already have a small orifice in there. I didn't have to make any new orifices on mine.

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