Results 1 to 5 of 5

Thread: RPM Help Needed

  1. #1

    Join Date
    Oct 2013
    Location
    West Central Florida
    Posts
    178
    +1
    12

    RPM Help Needed

    Ok, I finally got my XLT in the water after a long awaited rebuild. I used the Oside Bill recipe on the carbs and added the D plate, chip and free flow exhaust. everything went off perfect and she is now broken in and runs like a raped ape. My concern is that now she seems to want to rev out higher than it should (no cavitation problem), maybe from the extra power from the mods. I want this thing to last. Am I now supposta change the impeller and what rpm do I need to be turning at WOT. This is just a family ski and I am not looking for super speed. Thanks...


  2. #2

    Join Date
    Oct 2013
    Location
    West Central Florida
    Posts
    178
    +1
    12
    c'mon guys. all u Guru's out there and no one gives me 2 cents???

  3. #3
    I'm no GURU but in all my reading it seems like changing the impeller on a ski isn't much different than changing the rear gear in a race car, if you added a noticeable amount power to a race car, so much that all you where doing was spinning the tires more than a Rear gear change would be the next thing on the list of things to do. However tires spinning in a car is comparable to cavitation in a boat. If you truly don't have any cavitation than the best I can tell you is by changing out the impeller would help bring down the RPM @ top speed but might also hurt your hole shot or mid range acceleration. I'd like to see what the real Guru's have to say, I wouldn't think a carb tune and D plate would make such a huge difference in top speed/RPM. I wonder if a Rideplate and/or Intake grate would be money better spent.

  4. #4
    I am no expert but i understand the concept of the impellers. You want to size your impeller to be around 7100 to 7200 rpms... depending on mods. Of course once you go into triple pipes it all changes. Also might be a bit differnt if it has been ported as different porting will have different optimal rpm. At the end of the day you might have to test a bit. That said there are common used pitches based on mods. With your mods i would expect your rpms not to be too crazy as really they are all reliability mods more than anything. Did you do any porting or high compression? If not check your wear ring clearances. If it is worn you might be overreving. Get a small tach to double check your rpms

  5. #5

Thread Information

Users Browsing this Thread

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

Similar Threads

  1. Help needed identifying problems with no power until 5,000 RPM - 1200 SUV
    By jhawker23 in forum Yamaha PWC Performance (2-stroke)
    Replies: 15
    Last Post: 08-25-2016, 02:42 AM
  2. Low rpm's need help
    By hunt-dog in forum 4-Tec Performance
    Replies: 3
    Last Post: 08-02-2011, 08:19 AM
  3. Replies: 9
    Last Post: 08-08-2010, 01:40 PM
  4. Help needed 3200 rpm something is out of balance
    By wb1205 in forum Yamaha PWC Performance (4-stroke)
    Replies: 19
    Last Post: 07-16-2010, 07:47 AM
  5. 2000 Speedster w/Low RPM Stall - Need Help
    By gvernt in forum Sea Doo Sport Boats
    Replies: 3
    Last Post: 08-09-2007, 08:03 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
  •