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  1. #1

    Cool the 780 build is on

    got a train of though going on and wanted to see if i'm right the 650 750 and 780 all use the same bottom end as in crank and crank case and stator right? the water manifold is the same as well so if i got a 650 bottom end and if i put 780 jugs and pistons on it and build it like a 780 it will work right hulk crew?
    so the real problem is, i have a 650 compleate motor but its locked up so i was going to tear in to it and put a new crank in it and im going to buy the top end from sbt but they need cores so
    IF ANY ONE HAS ANY 780 JUGS OR PISTONS THEY CAN BE DAMAGED JUST NEED THEM FOR THE CORE NEED SOME GOOD HEADS AND ANY OTHER PARTS THAT ANY ONE HAS TO OFFER
    this is what i'm looking for
    used pistons-for cores (3)
    used jugs-for cores (3)
    some 780 carbs-rebuild able
    ill get new rings and jugs n pistons
    good heads (3)
    water manifold
    the updated cdi would be great
    780 jet pump
    pto coupler
    drive shaft
    i have the 650 hull make a sleeper ski
    need 780 exhast
    and the big header pipe
    some good reeds
    some one told me the 780 uses reed spaces well i need them to
    if i forgot something please let me know i'm new at this
    thanks for your help be looking for what the hulk crew has to offer


  2. #2
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
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    650/750/780 all use the same crank, yes.

    The 650/750 cases are slightly different from the 780 case.

    The 650 elec stator and flywheel will not work with a 780 CDI.

    Yes, 780 uses reed spacers.

    You don't need pistons to use as cores.

    650/750 carbs can be rejetted to work for a 780 (all 3 use the Mikuni SBN 38mm)

    What year 650 do you have now?

    Why not just buy my 780 kit I'm selling???

    http://www.greenhulk.net/forums/show...go!!!!!-Part-2

  3. #3
    so i cant use the 650 750 crank case to build the 780?
    whats your 780 kit selling for? and will that bolt to a 650 case? was going to use the 750 case but theres a crack in the water jacket so thats out to the scrap yard i got 2 750 hulls both are 93-94 and then i got a new to me 93 650 hull that i just got done doing a full rebuild on a 750 and droped that in the 650 one 750 hull i'm going to tear it down and try to get rid of it the other i'm going to look it over very carefully and see if i can rebuild that and drop this 780 in if not then im looking for a hull agan
    RIVER RATS PWC REPAIRS GO TALK TO CAMERON hes the best been playing with a 93 sl750 for 3 years and he fixed it for me in 2 sleepless nights come to find out who ever had it before me did not seal the crank case the water jacket was over following in to the crank case thats why my vaccum line was pumping water out of it

  4. #4
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
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    You CAN use a 650/750 case, it's just the 780 case has some internal porting. (no major problem using the 650 case)

    Kit is listed for $350 plus shipping, but will need to have cyls bored.

    Try to stay away from the 92 and 93 model year skis. The pumps were inferior to the 94 and newer modular style. And the cooling system was upgraded in 94.

  5. #5
    so am i going to lose power buy using the 650 case instead of the 780 case with the internal ports? do you have a 780 case laying around thats worth building? i didnt buy the 750 skis they was givin to me from a friend that could not figer it out and i been playing with it for 2 or 3 years and river rats got it fixed but anyways the 750 dont got no power so i want a 780 but keep running in to problems. i'm in dallas texas do you know about what shippings going to cost?

  6. #6

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    Ive got 44sbn carbs from a 785 on intake manifold, and with flame arrestor adapters and a 785 CDI that would be nice on that 780.

    Offers......

  7. #7
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
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    You might lose a tiny bit of power using 650/750 cases, but not alot.

    Sorry, no spare 780 cases.

    I was just explaining that the 94 and newer skis have much better designs over the 92-93 models.

    Shipping would be around $25. Any more and I'll cover the rest.

  8. #8
    so after i get the 780 kit from you xlint89 and the case n crank what would i be missing to finish the build that i need to track down beside the 780 pump n drive shaft? and thanks for coving the rest of the shippping cost.i wont get paid till the 18. the cylinders that need to be bored can i put new sleves in them? or do ther really need to be bored and how much bored do they need?
    RedlineR6 is it the complete cdi box where i can plug n play? with the stator and everything i need? never really bought parts so i have no clue what this stuff is worth. do you need any parts? i got some 750 and 650 engine parts and 2 750 ski

    i would like to get a newer ski but i just got this one running and something to start to look for in need of a double trailer if i really do get this 780 up n going.

    thanks for all your help

  9. #9
    i got a 750 on the water and it's ok for the kids but not alot of power after i get the 780 built am i going to see a bigger differance on the water?
    i would hope so its 30cc's bigger but u never know when your going in to a build blind

  10. #10
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
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    I have no idea what you have as far as parts, so i cannot tell you what you will need to finish.

    Cyls bored .5mm over size is what the pistons need. Boring cyls is WAAYYYY cheaper than resleeving them.

    750 = 80 HP (48 MPH)

    780 = 92 HP (52-54 MPH)

    So, not a HUGE gain, but a nice improvement,

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