Page 1 of 4 1 2 3 ... LastLast
Results 1 to 10 of 35
  1. #1
    race24x's Avatar
    Join Date
    May 2007
    Location
    Fayette, Maine
    Posts
    1,005

    Bad Performance SL750

    I am getting desperate looking for better performance out of my 95 SL750. It is bored .010 over has a 92 short dry pipe on it, an extended pump with a stock SL750 impeller. The only thing out of the ordinary is a stock 92 SL650 CDI and the fact that all of the parts are in a 92 SL650 hull but I thought the SL hulls are all the same. I did try to check the timing on the CDI with Xlint and thought this was the correct or better timing curve than the stock SL750 CDI. It seems to be pulling decent to its top end of 43 - 44 MPH but with the short pipe and extended pump I was hoping to get 52 - 55 MPH. So as you can see I am leaning towards the CDI but someone help me please LOL To me it feels like the motor is laying down not enough power to pull it up to max speed. Of course the old hull has no tach or anything to make it easier. I have messed with jetting until it looks perfect. Throw some ideas at me I can check it out. I have a post in the classified section asking to borrow a SL750 CDI just to try it for now I will buy one from someone if this helps at all but as some of you have seen I buy everyhting I see looking for the silver bullet to improve speed.


  2. #2
    SPEED KILLS, BUT YOU GET THERE QUICKER Keddano's Avatar
    Join Date
    Jul 2007
    Location
    Cedar Rapids,Iowa
    Posts
    6,381
    +1
    23
    Help the brother out someone.

  3. #3
    gorilla03's Avatar
    Join Date
    Sep 2006
    Location
    stevens point wi
    Posts
    3,774
    +1
    5
    I might have a solas 14/23 impeller for sale

  4. #4
    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
    I know you don't want to hear this, but you may need to update the elec. box to a newer one if it's the old style. Pretty sure a newer CDI will not work in that older box. I really thought that 92 650 timing curve would work well. Are there any other symptoms of performance loss other than low speed? Cavitation or something? If you're interested, I see someone is parting out his 95? 750. See what he wants for the complete elec system.
    Last edited by xlint89; 09-16-2007 at 02:23 AM.

  5. #5
    race24x's Avatar
    Join Date
    May 2007
    Location
    Fayette, Maine
    Posts
    1,005
    Thanks Gorilla but do you really think from the symptoms it is the impeller? Has anyone had a stock SL 750 only go 44 MPH I checked compression again mag 120 center 110 PTO 118 that all seems pretty good. I am going to try for the whole electric from the guy selling I really just wanted to borrow a CDI box or just CDI but I suppose I can part mine out if it doesnt get better LOL

  6. #6
    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
    44 MPH is normal for a 650, but low for a 750. Do you have any other problems? Is it hesitating or the pump doesn't seem to match the speed of the engine? I'm seeing if you're cavitating, or getting air into the jet pump. That would keep the speed down no matter what the engine was doing. The pump shoe was poorly sealed from the factory in the early years, matter of fact mine was doing it a few weeks ago. Also did you install the large O ring on the pump wear ring to seal the pump to the shoe?

  7. #7
    race24x's Avatar
    Join Date
    May 2007
    Location
    Fayette, Maine
    Posts
    1,005
    I have had a couple times the motor has really come to life when running out of gas etc that it really goes well all kinds of power revs higher then you know you are ruuning out of gas and switch to reserve. But I have messed with the jetting and dont think I should lean it out any as the plugs and wash look really good. There is a big O ring from the hull ( I think where the shoe is to the first part of the pump (the one held on by 4 1/2 bolts to the hull) but from that to the 4" extension no sealer nad no rings then from that to the stator no sealer no O ring then to the nozle no sealer no O rings. There was nothing in the pump I got and nothing in my 650 pump so I assumed there was nothing to put in there. It doesnt seem to be4 cavitating just like the motor is laying down not revving up and no top end power. That could be me though I need to ride another to see what the difference is. All of the others I am trying are like a 00 XP limited 06 F 12 Turbo Honda. They come out of the water like a rocket and are super fast. I did ride my buddies older 500 XP SeaDoo and mine is faster than his LOL. I can try the shoe I bought the sealer but havent used it yet. I need a tach to see what I am turning cause it just feels flat but maybe they do that to PWC motors the snowmobile motors really turn on.

  8. #8
    PolarisNut's Avatar
    Join Date
    Dec 2006
    Location
    Lower Michigan
    Posts
    1,809
    Quote Originally Posted by race24x View Post
    I have had a couple times the motor has really come to life when running out of gas etc that it really goes well all kinds of power revs higher then you know you are ruuning out of gas and switch to reserve. But I have messed with the jetting and dont think I should lean it out any as the plugs and wash look really good.
    If running out of gas makes that much difference, then the jetting HAS to be rich. I don't want to tell you to lean it out, and have you end up burning it down though. If you're jetted correctly, running out of fuel should make the motor run too lean, and lose rpm. Have you looked at the piston wash yet? Maybe pull a head off and post some pics.

  9. #9
    race24x's Avatar
    Join Date
    May 2007
    Location
    Fayette, Maine
    Posts
    1,005
    I did in one of the other posts and you could see it was a bit lean on pto and center and to lean on mag. plugs look perfect too chocolate milk brown I did several WOT chops Saturday morning I tried 2 turn richer just to see what would happen same speed. I didnt dare try a turn or 2 leaner cause they look so good right now. It has to be something dumb I am missing. The only 2 things that are SL650 1 the electrical box and 2 the dry pipe but the exhaust should work regardless right? So hence the trying to get a SL750 electrical box. I will punch myself right in the eye if I have been through all this and that fixes it though LOL

  10. #10
    SPEED KILLS, BUT YOU GET THERE QUICKER Keddano's Avatar
    Join Date
    Jul 2007
    Location
    Cedar Rapids,Iowa
    Posts
    6,381
    +1
    23
    There's a 780 ending today on E-Bay and this 750 ending tomorrow
    http://cgi.ebay.com/ebaymotors/Polar...QQcmdZViewItem

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. 94 SL650/SL750 Performance ??
    By frobate in forum Polaris Open Discussion
    Replies: 8
    Last Post: 05-07-2009, 11:04 PM
  2. 93' SL750 Compression Test...Good or bad???
    By dubstylguy in forum Polaris Open Discussion
    Replies: 20
    Last Post: 08-10-2008, 03:01 PM
  3. WTB: SL750 Performance Parts
    By Gadjet in forum Polaris Classifieds
    Replies: 6
    Last Post: 06-18-2008, 11:39 PM
  4. Parting out SL750 lots of performance parts
    By race24x in forum Polaris Classifieds
    Replies: 13
    Last Post: 05-28-2008, 05:45 PM
  5. Performance for the SL750
    By SantaCruz163 in forum Polaris PWC Performance
    Replies: 18
    Last Post: 05-24-2007, 10:50 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
  •