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  1. #1
    rob2337's Avatar
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    Fuji Budget Build

    Alright, over the winter I am collecting parts for my 750. My goal is to reach 60mph without triple pipes (Unless I find a cheap set on ebay .

    I am kinda following Group K's site in hopes that the 59.2mph they claimed without too major modifications is possible. Do you think it is possible?

    So far I have the following:

    SLX prop
    Boysen Reeds
    Extended pump (custom design )
    Ocean pro ride plate - O
    R&D Polaris version grate
    Reed spacers - to be installed
    Ocean Pro flame arrestors - to be installed
    Ocean Pro head - to be installed
    Choke delete with primer. - to be installed

    Basically everything on Group K's site minus porting for now.

    http://www.groupk.com/p750.htm

    If I can make it to 58mph with the above setup, I know I can swap the grate and plate for 2mph more.


    Any other cheap tricks for a Fuji??


  2. #2
    Lake Mead Bum & BTLS Mark starflight's Avatar
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    I think that w/o the porting you will fall a little short of your goal.
    I think it would be good for you to find a dry pipe for your ride in addition to your list of goodies.

  3. #3
    Click avatar for tech links/info, donation request K447's Avatar
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    Quote Originally Posted by rob2337 View Post
    ... Reed spacers - to be installed
    Ocean Pro flame arrestors - to be installed
    Ocean Pro head - to be installed
    Choke delete with primer. - to be installed...
    So the only major power adder is the aftermarket heads?

    What compression and fuel octane are you aiming for?

    Porting (and tuned pipes) is where most of the top end power usually comes from.

    Are you boosting the RPM limiter to allow higher peak RPM?

    Ocean Pro head - is that the head with the swirl patterns inside?
    Some guys think those raised ridges are a recipe for hot spots and poor combustion characteristics.

  4. #4
    rob2337's Avatar
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    Quote Originally Posted by K447 View Post
    So the only major power adder is the aftermarket heads? Reed spacers+ reeds + probably some porting

    What compression and fuel octane are you aiming for? 145psi 92 octane

    Porting (and tuned pipes) is where most of the top end power usually comes from.

    Are you boosting the RPM limiter to allow higher peak RPM? Not sure, limiter is at 6700 I think? I could try a slx cdi with the cut wire trick.

    Ocean Pro head - is that the head with the swirl patterns inside?
    Some guys think those raised ridges are a recipe for hot spots and poor combustion characteristics.

    So I have heard, I got it for super cheap on ebay, so I am going to try it.
    Also looking for other cheap mods.

  5. #5
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
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    The porting is what makes the most HP boost. I see that they also do a little carb work too.

    You've got pretty much the parts needed to make a SLX 780, why not make it a 780? That alone will gain you 12 HP over a 750.

    The OP "O" plate will also hurt top speed a little.

    Your parts list is pretty much identical to "her ride" and it's a 750. Only diff is, I was using a 6 vane SS stator and 12/18 impeller instead of a 15/20.

    The best I saw was 53.6 on GPS. WELL short of 60 MPH with stock 750 cyls and a bunch of bolt ons.

  6. #6
    rob2337's Avatar
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    Currently I have seen 54.4mph gps'ed in very cold weather.

    That is without the engine mods, only pump.

    Btw what makes the 12hp extra in a 780. It can't be the 20cc more.

  7. #7
    Bing-A-Ding-Ding-Ding, Brrrrrap! Brrrrrrrrrap!!! Polaris_Nut#1's Avatar
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    Quote Originally Posted by rob2337 View Post
    Currently I have seen 54.4mph gps'ed in very cold weather.

    That is without the engine mods, only pump.

    Btw what makes the 12hp extra in a 780. It can't be the 20cc more.
    It's different porting on the cylinders as well as different timing and CDI curve, plus the reed spacers and flame arrestors

  8. #8
    Bing-A-Ding-Ding-Ding, Brrrrrap! Brrrrrrrrrap!!! Polaris_Nut#1's Avatar
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    a stock (smooth/flat) SLX ride plate with a 6* wedge while hanging your weight off the back on water smooth as glass will help too

  9. #9
    Bing-A-Ding-Ding-Ding, Brrrrrap! Brrrrrrrrrap!!! Polaris_Nut#1's Avatar
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    Quote Originally Posted by rob2337 View Post
    Any other cheap tricks for a Fuji??
    your stock wet pipe is the same as the SLX change the cooling orifice from the 2.3mm 750 to the 1.0mm 780 and gain 200 rpm.

  10. #10
    Hayabusa's Avatar
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    Quote Originally Posted by Polaris_Nut#1 View Post
    It's different porting on the cylinders as well as different timing and CDI curve, plus the reed spacers and flame arrestors

    The upper case half on a 780 is also ported. If you can find a 780 case to use or duplicate the 780 porting on your 750 case, you might pick up a couple of ponies.

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