Results 1 to 4 of 4
  1. #1

    Join Date
    Jan 2013

    Angry Gp1200 r loss of rpm and top speed

    Ey guys!

    Bought gp 1200r stage II 3 months back done 18 hours on it no problems..
    Last time out noticed it was very boggy bottom end and about mid throttle it would take off and want to rip your arms off.
    Went home and realized the power valve servo motor wasnt making any cycle noise when u switch off, pulled out plug and found corroded terminal and a broken pin which must have shorted the servo motor out.
    Bought a second had pv servo motor tested it works fine, when i installed it and put the 2 cables on either end of pulleys, it keeps twitching really fast not cycling while and after the motor is running.
    Looked at service manual and found adjusting specs but the only way it will cycle is when the cables are really loose which still seems to turn the powervalve most of the way..
    So operation seemed fine just that the cables had to have alot of slack.

    Took it out on water today and bottom end is fast and jumps up on plane very quick but seems i lost my top end?
    so i disconnected servo plug and manually adjusted pv to fully open then fully closed but i couldnt get the rpm's to 7000!!
    It revs out at about 6800rpm and is nowhere near as fast as before???

  2. #2
    mudslanger's Avatar
    Join Date
    Jul 2010
    Huntsville Al
    It sounds like you are adjusting the powervalve cables incorrectly. check to make sure the 1 cable and 2 cable is in the 1 and 2 slot on the servo wheel and PV wheel. the easiest way to adjust the cables is to take both cables off the motor wheel then crank the engine on then off and when the servo cycles and you have the lineup hole pinned on the motor wheel. then install and adjust the slack out of the cables without forcing them on. Do NOT force them on you will turn the servo wheel getting it out of time with the PV wheel.

  3. #3

    Join Date
    Jan 2013
    thanks for info mudslanger, i figured the servo motor i bought was dodgy (hoping not my CDI), waiting on new 1 to get delivered then will get back on here

  4. #4

    Join Date
    Jan 2013
    Faulty pv motor, ski is whooping butt now!!

    Cheers guys

Thread Information

Users Browsing this Thread

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

Similar Threads

  1. Problem with RPM and top speed
    By rxp1972 in forum 4-Tec Performance
    Replies: 27
    Last Post: 07-17-2010, 03:02 PM
  2. Loss of RPM and Speed
    By medman in forum Sea Doo Open Discussion
    Replies: 8
    Last Post: 09-03-2008, 01:20 PM
  3. RXP-X Loss of acceleration and top speed
    By laarben in forum 4-Tec Performance
    Replies: 9
    Last Post: 07-31-2008, 03:15 PM
  4. loss of rpm and thrust after grate mod.
    By gp1200TX in forum Yamaha Old School Skis
    Replies: 19
    Last Post: 11-17-2007, 09:22 AM
  5. loss of rpm and power
    By gp1200TX in forum Yamaha PWC Performance (2-stroke)
    Replies: 2
    Last Post: 11-13-2007, 03:19 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