Results 1 to 8 of 8

Thread: RPM Reduction

  1. #1
    steved's Avatar
    Join Date
    Sep 2006
    Location
    UK
    Posts
    358
    +1
    14

    RPM Reduction Please help

    Out Yesterday Riding in alot of chop for many miles on return only 7800/7900 rpm before running 8150 with Jerry's washers and a Rotax SC wheel . Checked the clutch slip when hot with the SC in place by means for the nut on the wheel 4 nm so very low .

    Removed SC checked when cold 8nm , no signs of wear all measure up to spec even 5 washers are ok so re shimed back to 12/13 nm cold .

    Have done 15 hours since fitting metal clutch washers ? Have SS wear ring and all looks fine .

    Has this happend before to anybody . or is there more to look for, Does it sound like just the clutch ?
    Thanks
    Steve
    Last edited by steved; 07-15-2007 at 09:19 AM.


  2. #2
    Dont judge me...
    Join Date
    Jul 2006
    Location
    FLORIDA
    Posts
    610
    heat soak?

  3. #3

    Join Date
    May 2007
    Location
    Peoria,IL
    Posts
    30
    My 04 does the same thing. When I first take off I can turn 8000 no prob but after I ride for a while I can usually only get 7900 to 7950. I guessed it was some heat soak and I live in St Louis so it is usually fairly humid. I have checked my slip and I think I am at about 7nm so I guess I may need to shime and possibly replace the spring washers?

  4. #4
    steved's Avatar
    Join Date
    Sep 2006
    Location
    UK
    Posts
    358
    +1
    14
    Quote Originally Posted by SeanJ View Post
    My 04 does the same thing. When I first take off I can turn 8000 no prob but after I ride for a while I can usually only get 7900 to 7950. I guessed it was some heat soak and I live in St Louis so it is usually fairly humid. I have checked my slip and I think I am at about 7nm so I guess I may need to shime and possibly replace the spring washers?
    Thats possible for me I was surprised at the slip when it was hot or lack of it

    Steve

  5. #5
    Yamaha tow boat RIDEALLDAY's Avatar
    Join Date
    Feb 2006
    Location
    Texas
    Posts
    1,447
    I'm down ln the 7900 range also, but it's 95 degrees and humid. It's pissing me off. I'm scared to race anyone.

  6. #6
    Dont judge me...
    Join Date
    Jul 2006
    Location
    FLORIDA
    Posts
    610
    i live in north fl and it is hot here too, but i did get better results with a thermostat. it really does help alot.

  7. #7
    rior1's Avatar
    Join Date
    Feb 2007
    Location
    uk ESSEX
    Posts
    356
    steves the exact same thing happend to me ,on saturday rough as hell,i got smoked by 2 stock skis on smooth when we went over to kent,i ran a 64 on way in ,gave her a view runs and she went up to 68-69,i knew i was high on oil,i put it down to that,i have taken oil out havent run her yet but if you had same thing must have been something else,

  8. #8
    steved's Avatar
    Join Date
    Sep 2006
    Location
    UK
    Posts
    358
    +1
    14
    Quote Originally Posted by rior1 View Post
    steves the exact same thing happend to me ,on saturday rough as hell,i got smoked by 2 stock skis on smooth when we went over to kent,i ran a 64 on way in ,gave her a view runs and she went up to 68-69,i knew i was high on oil,i put it down to that,i have taken oil out havent run her yet but if you had same thing must have been something else,
    Sounds like it I rebuilt My SC and refitted it i have all the parts to re-shim it . Does not sound like oil to me , Mine was fine but can from Wat to Thorp and back to much chop for these. Let me know how you get on .

Thread Information

Users Browsing this Thread

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

Similar Threads

  1. 2013 FZS RPM Reduction in Choppy Water
    By PredatorVXR in forum Yamaha PWC Performance (4-stroke)
    Replies: 0
    Last Post: 04-16-2016, 07:43 PM
  2. Using Sante racing reduction pump (oil side) cone.. down on rpm
    By GasResearch-VT.SE in forum 4-Tec Performance
    Replies: 18
    Last Post: 02-01-2013, 05:11 AM
  3. New prop = excessive reduction in RPM (and performance)??
    By SuperChief in forum 4-Tec Performance
    Replies: 22
    Last Post: 11-03-2011, 11:00 AM
  4. RIVA Reduction Nozzle RPM question...
    By KeithKman in forum 4-Tec Performance
    Replies: 20
    Last Post: 09-10-2008, 12:03 PM
  5. Lost 1000 RPM with 15/20 and 81 Reduction Nozzle
    By excess in forum 4-Tec Performance
    Replies: 11
    Last Post: 09-02-2006, 03:02 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
  •