Page 1 of 2 1 2 LastLast
Results 1 to 10 of 11
  1. #1

    98 gp1200 carb ?

    Hey guys,I picked up a 98 gp1200 with the 3" riva flame arresters . The chokes are removed, primer kit installed and oil injector still hooked up. What carb settings, N&S, and jetting would you recommend .I am fixing to rebuild carbs and wanted to get everything done at one time. There are no other mods I know of. I think the previous owner just put the riva kit on it without making any changes to the carbs. The ski is running lean right now but could be due to the carbs needing rebuilt. Thanks , I know this is a very busy time for everybody.


  2. #2

    Join Date
    Apr 2006
    Location
    panama city beach 'fl
    Posts
    1,846
    +1
    9
    well stock carbs adj
    high speeds f-3/4 center 1 rear 3/4
    low all 1 turn
    high speed jets135
    low100 /95/97.5
    n/s 1.2
    only other thing I would do if apart -double up on high speed check valves and drill out return restrictors and run 100 main jet on #1 carb

  3. #3
    So stock settings on carbs are ok with the riva flame arresters?

  4. #4

    Join Date
    Apr 2006
    Location
    panama city beach 'fl
    Posts
    1,846
    +1
    9
    if nothing else done to ski just fatten up little bit ( these setting were pre ethanol fuel)
    what are setting now?

  5. #5

    Join Date
    Apr 2006
    Location
    panama city beach 'fl
    Posts
    1,846
    +1
    9
    if nothing else done to ski just fatten up little bit ( these setting were pre ethanol fuel)
    what are setting now?

  6. #6
    Not sure what they are at now but will check in the morning and set to specs,called riva tech and they gave me the same info you did. I took carbs apart today for cleaning and 2 of them were missing the diaphragms in the fuel pumps. I don't know how it even ran or didn't eat a piston. I will have it ready for the water again tomorrow and will let you know how it went . By the way what's your opinion on the oil injection Vs. pre mix on this specific ski. Thanks

  7. #7
    Yamaha artisan Cutlass's Avatar
    Join Date
    Oct 2010
    Location
    Madison, WI, USA
    Posts
    2,500
    +1
    55
    I run:
    135 mains out 1 1/2 turns:
    100 pilots out 1 1/4 turns.
    1.5 N/S and 115 gram spring.

  8. #8
    Thanks for the replies. I set the carbs at stock + 1/8 out for baseline . I went out for a w.o.t. run to see what the plugs would like . The ski took off great, went through mid to top good and then r.p.ms start to fall off so I shut it down.I tried to start it back up and idle to the trailer and the starter was dragging tried again it started and would get back on plain again. I pulled the the seat off and noticed the oil fitting had popped out of the front carb and the injector itself was leaking also. I took the plugs out and they were lean but no sign of aluminum on them or piston damage. I killed it as soon as i noticed the rpms fell but i know the reason it was dragging was from the heat and the piston expansion. I have an old cheap autozone compression tester and it was 110 on all three cylinders before I did the wot run but only 100 after but it could be the gauge . I am going to check it with a good snap on tester to see exactly what i am reading . I have never seen this happen and not score a piston or hole it . I am going to remove the injector in the morning and block it off , premix and see how it runs. The ski is showing 173 hrs. Has anyone else had this happen and the ski still run o.k?

  9. #9

    Join Date
    Sep 2008
    Location
    Clarksburg, WV
    Posts
    609
    +1
    1
    As far as the oil line coming off, it is very common and the main reason most everyone on here is premix.

  10. #10
    Yea, I am in the process of removing the the oil injection now and taking it to the water see how it does. A friend of mine has a saying " It might not have hurt nothing but it damn sure didn't help nothing either.'"

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. 98 GP1200 just rebuilt carbs but bogs @ low speed
    By NCMTS in forum Yamaha PWC Performance (2-stroke)
    Replies: 12
    Last Post: 06-14-2012, 05:21 AM
  2. Looking for clean used carbs for 98' GP1200
    By Fairway in forum Yamaha PWC Performance (2-stroke)
    Replies: 1
    Last Post: 07-18-2009, 08:05 PM
  3. FS: GP1200 Carbs-from '98- only $125.
    By jetmaniac in forum Yamaha Classifieds
    Replies: 17
    Last Post: 12-05-2008, 08:33 PM
  4. From 98 GP1200 to Ultra 250X
    By Scatman in forum Kawasaki PWC Performance (4-stroke)
    Replies: 11
    Last Post: 04-02-2007, 11:13 PM
  5. 98 gp1200 clogged fuel line, where to start?
    By spyder3000gtvr4 in forum Yamaha How To & FAQs
    Replies: 16
    Last Post: 09-11-2006, 10:27 AM

Posting Permissions

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