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  1. #1

    00 GP1200r Dont feel power valve boost

    Have a 00 GP1200r with some mods=solas/riva grate,ride plates/D plate/Worx sponson.Went for a ride last month and Felt a good boost while wound out for the first time out of the blue, must have been the power valves opening so all that day ski felt pretty good with power.Next time out no boost...So took carbs off and set low & high screws to factory because the throttle had to be feather pumped to take off after ski set a few...but dont think it helped....got settings from another thread said Low screws=1 3/8 turn and high screws=1 1/2,,,1 3/8,,,,,1 1/2 turns out if thats wrong let me know....So took for a test today and only felt boost one time the rest just felt like the ski was top out at 7000rpm...motor sounds great...power seems ok from start to W.open.....just might be me but when the ski seem to be top out it hit like a dirt bike powerband and Zoom you go...is that how the power valves opening feels... only felt it a few times within the month...to the test...I see the servo cables moving the P/v pulley a little, and when i cut off motor it moves a sec. Just seems it would turn P/v pulley more open when i gun it instead of it just a few cm lft and rgt..took cables off of pulley and turned the P/v pulley by hand felt pretty smooth till open all the way and turn back feels like its snagging on something....got the back off of servo and inside is spotless....Can the carb. setting cause it not to boost..or can the valves stick and not move even though pulley moves..took one cap off of power valve had a black coat of oil in it..would be greatful for any Help..sorry so long


  2. #2
    found a thread that sounds just like my problem but no answer...Thread=GP1200R 2001 Powervalve not opening 56 mph top speed

  3. #3
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    Check your compression

  4. #4
    A child of five would understand this. Go get one. pierowman's Avatar
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    P/V are not like a turbo where all of a sudden you feel some "boost". If the power curve isnt smooth than you need to look at possible issues. Like thatdude596 said whats your compression?

    When was the last carb rebuild?

    Also P/V sticking wide open means you need to take them apart and clean them. If your not already you should be using seafoam to help keep the p/v clean.

    Was the gas from last season? Did you add any additives to it?

  5. #5
    Thanks for replies..Update..Comp. 150 all 3........took the head and pv covers off to clean the pvs, and #1 and #3 move with ease but #2 pv moves ok in the middle but gets stiff when @ the bottom or top. Was going to remove and clean them but couldnt get it out..I took out both allen bolts popped out pin and looks like a sleeve carved in the cylinder on both side to prevent it falling on the piston like i thought it would and looks like the connecting shaft in it.. blocks the way out from the top..so do i have to pull the cylinder to remove it...So cleaned all of what i could get with carb. cleaner then lube the top pins with some 3 in 1 oil.....but #2 is still sticking all most like a grind instead of a smooth rub...and still dont know if that would cause the servo to no open them all the way....so just took out the small allen bolt that coonects it to shaft on all three and left the eaterclip on pins for insurance but them pins i had to knock out so pretty sure they are not moving...now im letting them free move with the exhaust flow......like a gas pv without the spring....tested it with pv covers off and they seem to be working good far as barely moving at idle and opening all the way when gun... I think i know the power diff. now before on acc. it would feel like a turbo hitting because it would randomly hit, now seems like the power always there as soon as you gun it...think it would be ok to ride them free like that or do you think they are moving to much and could wear and break easy..but far as test ski does great...felt like it fixed the taking off problem to..

  6. #6
    A child of five would understand this. Go get one. pierowman's Avatar
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    P/v dont come out from the cylinder side. There is an allen bolt that holds the sleeve in place. If youve removed that allen bolt then the sleeve and valve come out together this can take some force to remove especially if gunked up. I did a cleaning without pulling the valves and that ended up making things worse. I would remove all the valves and clean them all properly. The gunk is on the valve its self as well so you wont be able to clean it properly without removing them.

  7. #7
    i left the allen bolt in that holds a sealer tube thats between bottom and top of pv... took out the little one that mounts pin part to shaft that turns with servo...does the silver shaft have to come out before removing or will it pass by.....

  8. #8
    A child of five would understand this. Go get one. pierowman's Avatar
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    The little one that mounts the pin to the shaft is first allen bolt that has to be removed. You then have to remove the shaft from the case. Then you have to remove the allen bolt that holds the P/V sleeve in the case. P/V and sleeve comes out as one piece.

    For this process, youll need new oil seals and circle clips for the shafts.

  9. #9
    thanks for the instructions....looks like the manifold has to come off to have enough clearance to pull out since its the middle cylinder...So took pv covers off again after a few rides with them free flowing and #2 is a lot easier to move now so put all bolts back in and put new servo cables on because they were in bad shape which could have been part of the problem to...Seems to be working good i picked up 5mph.....from 53 to 58 on ski display which is prob. not accurate so im going to GPS it soon...already done the pistons when 1st got it because #3 was busted from lack of oil from them putting a oil blocker on it and diaphram in carb was bad...going to tear down again this winter and replace pv oil rings and clean pvs the right way thanks.....sorry off the subject which do you think is better a steel or rubber wear ring i have a factory steel one but i can see a good bit of clearance around it still goes great but was thinking it needs to be real close...i have a solas imp. that looks new still, and riva ride plate/grate ,works sponson with D.plate

  10. #10
    A child of five would understand this. Go get one. pierowman's Avatar
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    Note i was able to get them out without taking the manifold off but i hear its easier if you do take it off.

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