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  1. #1

    02 RXDI with 120 compression

    I love my RXDI..( 951cc / 2 stroke ) It has 206 original hours.. and still looks new. It runs great.. but it has only 120 psi per cylinder..so it will soon need a ring/head job I would assume?

    I was wondering does anyone know if this is something that can be done by myself? I know the DI's are a bit challenging with the fuel rail , ect.. , I took this to a shop last year and got a quote of $3000.00 to rebuild the whole motor.. but decided to buy a new Spark instead.
    In any case.. I may try to put new rings in myself .. get that compression back up to where it should be.

    So my question is... In short.. what exactly needs to be done ? and who has done this on an RXDI before? How much did it cost and was it easy or rather difficult? Does the motor have to come out of the ski or can it be done from inside?

    Thank You in advance ! Greenhulk always has all the answers !

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  2. #2
    I would think you just can't re ring and call it a day, especially at that many hours when the bore is probably out of round. Best thing might be to get a trade in set from sbt and use them if the crank is within limits ( you can at least check the gap between the rod washers and the journals to get an idea of how good it is still ) unless you have a trusty borer. you can't just buy a set larger pistons because there is no guarantee it will be round at that bore. you would have to measure how out of round it is with a bore gauge ( calipers will give you the measurements at the top of the cylinder which can give you a good idea but the best thing is to know how much it is out of round at all points ) . that's why a set where somebody has already done that might be the best bet.
    by the way how does that spark compare to the RXP which is the descendent of my beloved but not trusty GSXL ? With all the problems i' m having with it I think the spark might be just the ticket for reliable fun if you can get a bit more HP out of it ( I would like to at least get to 55 MPH reliably )

  3. #3
    Thanks for the response ! Not sure if that sounds that easy... On the other topic.. The Spark is a hella of a ride.. Of course I pretty much have it fully moded.. V tech tune 109hp..straight rear exhaust , Intake grate, ported waterbox, .. ect.. Its so quick and nimble.. Top speed is around 49-51. But I have to admit, I thought I would really miss the 60 mph ( RXDI ) .. but I have been totally satisfied with the Sparks top speed... mainly because on how sensitive the throttle response is.. and the way it handles is great. It totally put the FUN back into a SEADOO. I was not a big fan of the looks of the Spark either.. kinda cheap plastic look.. well I fixed that too... Nice custom glossy pearl paint job.. now it looks more like a fiberglass ski.. and it still weighs 285lbs less then my RXDI... LOL Trust me.. you wont be disappointed.

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  4. #4
    Myself's Avatar
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    120-130 psi is just fine for the 951. What problems are you experiencing with it?

  5. #5
    gp1200rider's Avatar
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    Iv seen them stock with 110-160 , if its still running why bother run it till it dies , I would put oil in the counter balancer tho .Iv seen alot of the DI loose compression on the front cyl first ?

  6. #6
    Nothing wrong with it yet.. just thinking it may be soon. Compression was 145 when I bought it in 2010. Runs great right now.

  7. #7
    Myself's Avatar
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    It's been my experience that the DI and RFI loose compression on the front cylinder due to fuel pressure loss. The simple design of the fuel rail will put more pressure at the dead end, then build backwards......unless there isn't enough fuel pressure to build back up quick enough before the front fires off again. This will be more apt to cause destruction at higher RPM's. Do yourself a favor and change out all 3 fuel filters.

  8. #8
    gp1200rider's Avatar
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    Good to Know ....Usually when I get them its for repair and there already DOA , I think its the worst motor design for a ski ever made, I cant believe they used them in ULTRALITES .

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