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  1. #1

    Hesitation until RAVE valves kick in

    Hey all -

    I have a 98 GSX Limited with a 15 hour old 951 in it
    Mods:
    ADA Racing 50cc Domes
    Jetting is 95 lows and 167 mains with 2.3 needle and seats with stock springs and no accel pump (as per Ben's 951 mods)
    Low jet 1.5 out, hi jet .3/8th of a turn out )
    Solas 15/20
    Prok filters
    RAVE caps on both the cyl and the water box are flush

    My boat is a little slow to get out of the water (i need to turn my low jets in some i think, it has a bog before it opens up) and between like 5200 - 5500rpm .... once the RAVEs open its like a bat out of hell all the way to 6750rpm (i think the low RPMs are a function of my weight - 260lbs, and being over propped, im looking for a 13/19 or something of that nature to help out with that)

    Is there any good reason that the RAVEs would hesitate to open like that? Lack of vacuum (i see the vacuum solenoid looking thing that the valves hook to). I never rebuilt the RAVEs when i rebuilt the motor so i dont know if that could be a factor?

    any ideas greatly apreciated!


  2. #2
    96XPSS's Avatar
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    Your RAVES may be stuck open? The rpms you mention are when they are supposed to open, and if they open sooner, bottom-end absolutely sucks.

    You do appear to be overpropped, and could be overly rich. But..."all of a sudden running like a bat outta hell" sounds like the RAVES are stuck open.

  3. #3
    Quote Originally Posted by 96XPSS View Post
    Your RAVES may be stuck open? The rpms you mention are when they are supposed to open, and if they open sooner, bottom-end absolutely sucks.

    You do appear to be overpropped, and could be overly rich. But..."all of a sudden running like a bat outta hell" sounds like the RAVES are stuck open.
    how would i go about un sticking them?

  4. #4
    KrunchovXPL-GTX-RX's Avatar
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    +1 on the RAVEs and the overprop (6750 on top is a bit low).

    Take the caps off and see if they move out or in or what have you. They should move smooth. If not, time to pull them out, apart and clean. Get new orings and stuff too.

  5. #5
    4ringturncoat's Avatar
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    Remove the pulse lines to the raves and try it out, it it still the same then it is the raves, if it is worse then your problem is jetting.

  6. #6
    Quote Originally Posted by 4ringturncoat View Post
    Remove the pulse lines to the raves and try it out, it it still the same then it is the raves, if it is worse then your problem is jetting.
    I emailed ben himself, and he said that if anything, i should turn my high screws shut....too much fuel could be killing my top end right?

  7. #7
    96XPSS's Avatar
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    Quote Originally Posted by radeon View Post
    I emailed ben himself, and he said that if anything, i should turn my high screws shut....too much fuel could be killing my top end right?
    Have you ever heard of a plug chop? This is how you determine if the fuel mixture is correct. Every ski is different, as is the weight of the rider. We can advise you places to look to find your lost rpms, but you have to do the work to confirm.

  8. #8
    4ringturncoat's Avatar
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    Quote Originally Posted by radeon View Post
    I emailed ben himself, and he said that if anything, i should turn my high screws shut....too much fuel could be killing my top end right?
    You could try to lean it out a bit, your jetting looks ok, but not to crazy rich. Check you raves first. What does it do it you go about 4000 rpm and pin it? Does it wallow or come off clean? With the jetting you have it should be pretty close. If you close the hs screw it will lean it out from about 5/8-3/4 throttle, it might be enought to help if you are rich in the middle. But with the 95's you should be close.

    Does it hesitate if you pin it from a idle or do the rpms rise slow but clean?

  9. #9
    If i just gun it from idle .... sometimes it will just die if ive been idling at all, other times it will be quick to like 5000rpm and then have a hard time from 5000 - 5500, but once the RAVEs open its great to to the max rpm i get.

    So im almost wondering if my idle mix is too rich at 1.5 turns out ...

  10. #10
    96XPSS's Avatar
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    Yes, you ae rich at idle. As the screws are on top, how hard is it to go in 1/2 turn and see how she runs? And what about a plug chop?

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