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

    Join Date
    Jul 2013
    Location
    Kansas City
    Posts
    58

    95 ZXI 900 carb adjustment for low end power

    Hey Guys,

    I've had a 95 ZXI 900 for about 3 years now. Runs great and is a beast wide open. However when idling in the water when you first get on the gas it's really dead kind of like its bogging and the RPMS will lift and then suddenly it clears out and takes off full of power.
    If you release the throttle completely and get right back on it's snappy but let off and let it idle for a couple seconds or more then same thing.

    At home when I fire it up out of the water and blip the throttle it's super responsive and RPMs rap instantly and snappy. So clearly it changes when in the water. How do you guys tune that? What's happening under load in the water? Is it going rich or lean? I'm not really sure how to tune the carbs when I can't simulate the problem at home on the trailer.

    Also should I get a set of sync tubes to tune the carbs in sync? It makes sense. I remember using those back in the day on my old 4 cylinder street bikes.

    Thanks for any pointers
    Malcolm


  2. #2
    steve45's Avatar
    Join Date
    Feb 2008
    Location
    Texas
    Posts
    5,998
    +1
    432
    Well, when you have it in the water, the engine is actually doing work. On the trailer, it's making noise and only making enough power to overcome internal friction.

    The carbs are usually set up a little rich from the factory. This is to keep it from running too lean and getting hot, but doesn't give the best performance.

    You can let it idle (in the water) for about 3 or 4 minutes, then pull the spark plugs. If they're black/wet, lean that cylinder's low speed screw about 1/16 turn (CW). Take it our and run it at full throttle for a couple of minutes to clear the spark plugs, then do it again. It may take an hour or two to get it right.

  3. #3

    Join Date
    Jul 2013
    Location
    Kansas City
    Posts
    58
    I'd venture to guess yes to rich because the plugs always look black and wet. I'll try a little leaning on them and see how that goes.

  4. #4

    Join Date
    Jul 2013
    Location
    Kansas City
    Posts
    58
    BTW I did adjust my carb just a few days after your suggestion and it helped out a lot. It's a pain in the butt as you have to completely unbolt the carbs, after removing the air cleaner box, and pull them up and turn over on their sides to access the screws but I leaned each one out a hair, about 1/16th of an inch on the low side and its much more responsive in the low end now once fully warmed etc.

    Thanks again.

  5. #5
    steve45's Avatar
    Join Date
    Feb 2008
    Location
    Texas
    Posts
    5,998
    +1
    432
    Glad it's running better! The 900s are a pain to adjust. I bought some long screws to mount the carbs, put some screen over the top to serve as a flame arrestor, then was able to adjust them without having to mess with the flame arrestor. If I remember correctly, I was able to adjust them without removing the carbs by using a 1/4" hex drive screwdriver bit and a 1/4" open end wrench.

  6. #6

    Join Date
    Jul 2013
    Location
    Kansas City
    Posts
    58
    Mine has this huge R&D box on top of the carbs. So I have to remove that first then unbolt carbs and slide up and turn over. Not a big deal. It's done and running better


  7. #7
    Hello to all! I use this key here, to regulate the carburetors. I'm also having trouble regulating my 900, funny that the candles are dark but not wet, but when I put maximum acceleration it does not develop and at low the engine usually dies when it goes out. Funny that I noticed that this fuel is coming back through the vent cup that separates the water from the gasoline so that water does not fall into the tank. if it is turning too much fuel by the return can it be clogging in the carburetor? this my engine is adapted nun 650 sx, using his tank. Somebody help me please.

  8. #8
    Hello to all! I use this key here, to regulate the carburetors. I'm also having trouble regulating my 900, funny that the candles are dark but not wet, but when I put maximum acceleration it does not develop and at low the engine usually dies when it goes out. Funny that I noticed that this fuel is coming back through the vent cup that separates the water from the gasoline so that water does not fall into the tank. if it is turning too much fuel by the return can it be clogging in the carburetor? this my engine is adapted nun 650 sx, using his tank. Somebody help me please.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	20170423_114644.jpg 
Views:	69 
Size:	69.3 KB 
ID:	420806   Click image for larger version. 

Name:	chave regulagem do ar 2.jpeg 
Views:	38 
Size:	9.8 KB 
ID:	420807   Click image for larger version. 

Name:	chave regulagem do ar 1.jpg 
Views:	40 
Size:	14.5 KB 
ID:	420808  

  9. #9
    steve45's Avatar
    Join Date
    Feb 2008
    Location
    Texas
    Posts
    5,998
    +1
    432
    That looks like a nice setup for adjusting those carbs! Is there enough room to get the tool in between them?

  10. #10
    Wrench's Avatar
    Join Date
    Nov 2010
    Location
    Lawrence, Kansas, United States
    Posts
    183
    Quote Originally Posted by MalcolmV8 View Post
    Mine has this huge R&D box on top of the carbs. So I have to remove that first then unbolt carbs and slide up and turn over. Not a big deal. It's done and running better

    Waking up an old thread here.......

    I am searching for the high/low speed factory setting for a 1998 STX 900.

    Thanks for any help.

Page 1 of 2 12 LastLast

Thread Information

Users Browsing this Thread

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

Similar Threads

  1. Spark plug gap for 95 ZXI 900?
    By MalcolmV8 in forum Kawasaki Open Discussion
    Replies: 3
    Last Post: 08-02-2013, 05:04 PM
  2. WTB - Parts WTB Starter Relay For '95 ZXI 900
    By flnz400 in forum Kawasaki Classifieds
    Replies: 0
    Last Post: 12-01-2011, 05:13 PM
  3. Is there a Prop for Low end power? Waterskiing?
    By majundecid in forum 4-Tec Performance
    Replies: 7
    Last Post: 06-17-2008, 08:46 AM
  4. 95 ZXI 900 No Spark
    By Speedy4 in forum Kawasaki Open Discussion
    Replies: 3
    Last Post: 11-27-2007, 06:01 AM
  5. 12/20 best for low end on a 03 gtx sc?
    By lextoy in forum Sea Doo Open Discussion
    Replies: 3
    Last Post: 10-31-2007, 05:22 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
  •