Page 1 of 2 1 2 LastLast
Results 1 to 10 of 12

Thread: 1998 gp1200

  1. #1

    Angry 1998 gp1200

    I have a 1998 gp1200 and it having such a big.motor its not.doing what I expect. Everyone with bigger skis with smaller motors are killin me. Ive cleaned all carbs checked intake grate, ride plates good.. But it wont even reach 50. The only things its missin is the two white pieces on the bottom but they wont affect the holeshot.. It like it revs about 7000 rpm which is.right. But its kinda slow. Unlike my other gp1200. The only thing I can.think of is the wear ring which could.be it. I haint checked it yet. But if anyone has any nm idea or has the same prob. Please help. Thanks.


  2. #2
    Someone please help

  3. #3

    Join Date
    Sep 2008
    Location
    Clarksburg, WV
    Posts
    609
    +1
    1

    1998 gp1200

    Is that a gps speed or the speedo speed? If its the speedo you could actually be doing way less or more. The trim tabs missing will create drag any time the ski is moving from holeshot through top speed. Acceleration will be reduced due to drag.
    Replace the trim tabs with some aluminum ones.
    Check the impeller to wear ring clearance with a feeler gauge (.01-.014)
    Check compression in all cylinders

  4. #4

    Gp1200

    it had 120 on all cylinders and wear ring distance from impeller is right. The only thing is the trim tabs is I guess what there called if there two white things on the bottom are missing but would that affect the holeshot. Its hittin about 7000 rpm so idk what it could be b

    esides that. Thanks

  5. #5
    Yamaha artisan Cutlass's Avatar
    Join Date
    Oct 2010
    Location
    Madison, WI, USA
    Posts
    2,500
    +1
    55
    Is the impeller bent, dinged up, or the incorrect pitch for the ski? Is the ski completely stock?

  6. #6

  7. #7
    I took it apart yesterday and everything looked fine. Its what came on it so I reckon its the right pitch. I just dont understand why my brotherS 96 seadoo gtx thatll about beat me.ive thought about premix but didnt know if it was really worth it.

  8. #8
    Yamaha artisan Cutlass's Avatar
    Join Date
    Oct 2010
    Location
    Madison, WI, USA
    Posts
    2,500
    +1
    55
    Hard to say. Either the engine isn't making full power, the jetpump has issues somewhere, or the hull/rideplate is creating alot of drag in the water.

  9. #9
    Will the trim tabs really affect it this bad? And I heard somethin about taking washers or something off the back of the ride plate?

  10. #10
    Yamaha artisan Cutlass's Avatar
    Join Date
    Oct 2010
    Location
    Madison, WI, USA
    Posts
    2,500
    +1
    55
    if the tabs are completely gone, then no, not really.
    If they are partially there or hanging down then yes...it'll pull your top speed down.
    If the ride plate is shimmed with washers in the back two bolts it will slow you down some.
    Maybe take some pics of the the intake grate, ride plate, and trim tab areas and post them up.
    The other thing I thought of is maybe the pump stator vanes are damaged.

Page 1 of 2 1 2 LastLast

Thread Information

Users Browsing this Thread

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

Similar Threads

  1. 1998 GP1200 triple finally done! Well almost!
    By krispaintballz in forum Yamaha Old School Skis
    Replies: 1004
    Last Post: 12-15-2015, 02:06 AM
  2. F/S 1998 GP1200 with many new parts in Atlanta
    By tfergusonracing in forum Yamaha 2 Stroke Skis
    Replies: 12
    Last Post: 08-03-2008, 01:35 AM
  3. F/S 1998 GP1200 with many new parts in Atlanta
    By tfergusonracing in forum Yamaha Classifieds
    Replies: 11
    Last Post: 07-21-2008, 01:43 PM
  4. 1998 GP1200 w/ trailer blown motor (bad core)
    By gixxer92 in forum Yamaha Classifieds
    Replies: 12
    Last Post: 05-15-2008, 11:36 AM
  5. Newbie Question about handlebars on a 1998 GP1200
    By CJean386 in forum Yamaha How To & FAQs
    Replies: 5
    Last Post: 06-01-2007, 12:18 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
  •