Page 1 of 3 1 2 3 LastLast
Results 1 to 10 of 21
  1. #1

    sl780 PSI tripple pipes

    Finally, got time to take the polaris 780 out! If you guys remember I did a bunch of mods to it. It ran a little sluggish up to half throttle and after half throttle it didnt pull any harder. I turned in the low end screws in and it got better (started pulling on the low end almost like it did when it was stock) Still no top end. I think it still fat up top. I turned in the high speed screws and it got alittle better. The plugs were black around the out side and lite tan in the center. Running it at half throttle it still said that it was going 53-54 mph around 6300-6600 rpms. Got to late to do any more. But put it on the trailer and hit the throttle to blow the water out of the pipes and it started to rev Like wide open! I hit the kill, but it stayed running! Had to shut the gas off to stop it. WOW that got attention! At least it didnt throw any rods. Heres some of the some mod done,
    PSI tripple pipes
    pro 44 carbs
    cut heads
    97 pro ign
    12-17
    bored nozzle
    stock reeds
    bore and ports are stock
    long pump


  2. #2
    My ski wont go above 1/2 throttle as well, and it was going WOT on me with no spark plugs connected...

    Still trying to figure out whats up with it, lol.

  3. #3
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
    Join Date
    Oct 2006
    Location
    Cleveland OH
    Posts
    17,330
    +1
    31
    YAY!!!!!!!!!! Welcome back dirty....

    What year carbs are you using? what's the jetting at?

    Lose the 12/17 and go with a 13/18 at least, I'm running the SLX 15/20 on mine.

    Ditch the bored nozzle. You'll have all kinds of HP now for an awesome holeshot. Besides, the bored nozzle acts like stepping the impeller down 1 size. Kinda like you'r running a 11/16.

    Get some reeds for Pete's sake!!! The pipes like to run right around 7000 RPM, stock petals won't take that kind of abuse for too long. Carbon Fiber my friend.

  4. #4
    Bing-A-Ding-Ding-Ding, Brrrrrap! Brrrrrrrrrap!!! Polaris_Nut#1's Avatar
    Join Date
    Aug 2006
    Location
    Pittsfield, MA
    Posts
    3,350
    +1
    26
    Quote Originally Posted by Dirtykiddracing View Post
    it started to rev Like wide open! I hit the kill, but it stayed running! Had to shut the gas off to stop it. WOW that got attention! At least it didnt throw any rods.
    That's called glow plugging like a diesel engine. It's not good. Usually from a lean condition.

  5. #5
    Bing-A-Ding-Ding-Ding, Brrrrrap! Brrrrrrrrrap!!! Polaris_Nut#1's Avatar
    Join Date
    Aug 2006
    Location
    Pittsfield, MA
    Posts
    3,350
    +1
    26
    Quote Originally Posted by ZOMGVTEK View Post
    it was going WOT on me with no spark plugs connected...

    Still trying to figure out whats up with it, lol.
    That's called glow plugging like a diesel engine. It's not good. Usually from a lean condition.

    You should both do compression checks to make sure you didn't scuff a cylinder

  6. #6
    X,
    Im running a 125 pilot and 95 main jet Not sure what year the carbs are. I do have other reeds, I can throw in. Did you get yours running good?

  7. #7
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
    Join Date
    Oct 2006
    Location
    Cleveland OH
    Posts
    17,330
    +1
    31
    Those sound like 98 and newer PRO carbs. My 97's use a smaller pilot with a BIG main.

    Mine's running really good, just need to figure out the idle and take off jetting though. (hard starting and hesitation)

    Pulls like a SOB from 4200-6700+ RPM.

    I have the V Force II's set up for high tension.

  8. #8
    I used PSI specs for jetting.

  9. #9
    I will compression check and see were its at. Hopfully there good.

  10. #10
    PolarisNut's Avatar
    Join Date
    Dec 2006
    Location
    Lower Michigan
    Posts
    1,809
    If a 2 stroke ever runs away like that, you can usually snuff it out by snapping the throttle open and closed a few times, or pulling the choke lever. It is NEVER, EVER a good idea to try to run it wide open on the trailer. It will never run away when its loaded in the water, unless the throttle gets stuck open.

Page 1 of 3 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. Pressure Testing Tripple Pipes
    By ABBOTT in forum Yamaha How To & FAQs
    Replies: 0
    Last Post: 07-28-2006, 04:10 PM
  2. TUNERS WHERE ARE YOU....Tripple pipes and prop combination
    By JOSE13RT in forum Yamaha PWC Performance (2-stroke)
    Replies: 2
    Last Post: 07-16-2006, 11:55 PM
  3. Tripple Pipes / MSD + More - Thanks Andy!!
    By ABBOTT in forum Yamaha PWC Performance (2-stroke)
    Replies: 20
    Last Post: 07-08-2006, 10:18 AM
  4. Only Tripple Pipes
    By GPRsmartarse in forum Yamaha PWC Performance (2-stroke)
    Replies: 6
    Last Post: 05-29-2006, 09:59 AM
  5. Tripple piped GPR to RXP
    By Insanediego Joe in forum Sea Doo Open Discussion
    Replies: 13
    Last Post: 05-14-2006, 12:09 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
  •