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  1. #51
    Myself's Avatar
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    Quote Originally Posted by AL_Mark View Post
    Hey Myself. The NADA says this motor put out 110hp. That's damn good for 782CCs for back in the 90s. How did they get that HP out of it? RPMs? Do you think it they were honest on this HP? You seem to view them as reliable. To get this HP, Yamaha had to go to 1052 CCs.
    Yes, 110hp is correct. The '96xp bone stock on smooth water will do an honest 58mph GPS. The Rotax design with rotary valve definately makes more power per cc than the rest. It's also a power valve design which allows much more radical porting without sacrificing low end. And of course with a balance shaft the engine is much smoother operating than others also lending to a longer lifespan. The 787 with mild porting, milled head, lightened flywheel, aftermarket pipe, jetting and F/A will be pushing 150hp and STILL as reliable as a stock one!

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  3. #52

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    There are a few of these for sale in my neck of the woods. I may get one and put it in my Jonski. Just don't have any experience with a Rotax. Is it sort of a supercharger or something? This rotax has pistons, and the word rotax, I envisioned something like a rotary engine. But rotary engines are not known for their torque, but they make up for it in RPMs.


  4. #53
    HHpotatoechips's Avatar
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    Quote Originally Posted by AL_Mark View Post
    That is what I am thinking "myself". HAHA I crack myself up sometimes!!! Another pun. But is it worth putting money into this old 787? Probably going to need a new crank.
    I feel like that depends a lot on you and what you're interested in doing. Feel like dropping scratch on your ski or paying for a new one?

  5. #54
    This is how I run a jetski shop in the desert nmpeter's Avatar
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    Just sayin the 787 seadoo is a damm good powerplant, couple it with the first gen xp hull and its a virtual pwc hotrod..IF you can handle it.

    Personally I prefer the 97gtx hull handling wise, but I'm kinda old..and was back when I opened my shop in '08, but still the 97/787 was a ski I always wanted to lake test, even with my test tank at the ready

    Now in answer to the question...It's all about the hull and other running gear..if its in good to excellent shape, by all means a refreshed engine can give you several years of inexpensive fun. with fuel prices on the rise, you get a darn good bang for the buck with he 787 powerplant

    its it is a beat yard queen, then maybe not.

    and to add a little to the rotax heritage, the rotary valve two stroke engine is not unique to seadoo, back when I was really young I owned a yamaha 80cc scrambler that used a rotary valve engine, it had no problem bringing me up to highway speed and still provide 50+ MPG.

    Rotax also made small aircraft engines of numerous configurations, it had nothing at all to do with rotary engines, AKA the "wankel" That design suffered a early demise when the price of fuel spiked in the early 80's as it could never lick the poor fuel economy and excessive emissions that plagued its unique design

    The so called "boxer" engine design which was used on early VW beetles, BMW motorcycles and subaru automobiles is one of the more successful engines that didn't follow standard conventions like the straight 6 or v8 motors.

    limitations of hulls really kept most alternative engine designs out of the marine business, but innovations such as balance shafts allowed older designs to flourish for a decade or more

  6. #55

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    I have been doing a little more research in this rotax design and reliability. Looks like we may have the only 2 or 3 rotax fans chiming in on this thread. And they all are in business of fixing PWCs. Good business I believe. Others have noted that they try to keep one running! Maybe I will keep to my Yamahas. All of mine run.

  7. #56
    Myself's Avatar
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    Quote Originally Posted by AL_Mark View Post
    I have been doing a little more research in this rotax design and reliability. Looks like we may have the only 2 or 3 rotax fans chiming in on this thread. And they all are in business of fixing PWCs. Good business I believe. Others have noted that they try to keep one running! Maybe I will keep to my Yamahas. All of mine run.
    It's because there are hardly any 2 stroke riders at all on this forum, they are mostly on PWC Today. Yamaha 2 strokes are hands down the MOST reliable.....BUT, it's because they are relatively downtuned in stock form. The Seadoo's were more high strung and just will NOT put up with lack of maintenance like a Yamaha will. If you want a good comparison, put the Yamaha 800 and 1200 powervalve engines in the same boat as ANY Seadoo 2 stroke. A bit of neglect and either one will leave you stranded.


  8. #57
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    Quote Originally Posted by nmpeter View Post
    and to add a little to the rotax heritage, the rotary valve two stroke engine is not unique to seadoo, back when I was really young I owned a yamaha 80cc scrambler that used a rotary valve engine, it had no problem bringing me up to highway speed and still provide 50+ MPG.
    I had a Cox .049 model airplane engine that had a rotary valve--60 years ago!

  9. #58

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    Quote Originally Posted by Myself View Post
    It's because there are hardly any 2 stroke riders at all on this forum, they are mostly on PWC Today. Yamaha 2 strokes are hands down the MOST reliable.....BUT, it's because they are relatively downtuned in stock form. The Seadoo's were more high strung and just will NOT put up with lack of maintenance like a Yamaha will. If you want a good comparison, put the Yamaha 800 and 1200 powervalve engines in the same boat as ANY Seadoo 2 stroke. A bit of neglect and either one will leave you stranded.

    Yes I have 2 of those PV1200s and I agree with "Myself" on the need for maintenance. But why in the world did they make it so you can't even get to the the carbs to do the maintenance or inspections. Barely gave room to change the plugs. I am about ready to cut a hole in the side of the body for access and reseal with a removable panel.

  10. #59
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    Quote Originally Posted by AL_Mark View Post
    Yes I have 2 of those PV1200s and I agree with "Myself" on the need for maintenance. But why in the world did they make it so you can't even get to the the carbs to do the maintenance or inspections. Barely gave room to change the plugs. I am about ready to cut a hole in the side of the body for access and reseal with a removable panel.
    Sure sounds nice, Honda sure did their buyers a favor on the Aquatrax.

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