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    performance mods?

    1978 GS750E

    What changes upgrades performance mods can i make to my bike i want it street fightered, im not too fussy about tope end speed a previous owner said he had it at 120mph that'll do for me.

    so far i have just added a 4/1 harris pipe(still need to rejet) what else can i do to beef it up, im not looking for indepth answers just hints\tips(then ill ask for indepth )

    im a bit lost when it comes to gear ratios etc but ive spent all afternoon searching forum and still not sure wat mods can be done

    thanks

    #2
    Ah, you picked a great bike to start with.

    STEP ONE: Make sure the bike works! Check, adjust, lube everything. No point in trying to tune your carburetion if your ignition is weak, for example.

    First, pick a good 4-1. I don't have any experience with Harris, but I heard they make good stuff. If not them, buy a V&H pipe:



    Then, make the carbs work. Decide if you want to ditch the airbox (I always do) and go from there. If you go pods, buy the K&Ns. I don't know if they make a jet kit for your year, but if they do it'll make jetting a whole lot easier. If they don't, you may want to keep the airbox.

    Then ditch the points and coils, go with a Dyna S ignition:



    and coils:



    At about this time you'll be thinking, "man, this suspension sucks" and you'll be right.

    Here:

    Fitting & Adjustment Instructions for Ikon Stereodampers Type 7610 and 7614.For further Shock Absorber Specifications please see view


    for the rear,

    Here:



    for the front.

    Most people go with SS brake lines, they help a little. Mostly they look bitchin:

    http://www.galferusa.com/MOTO.html I like Galfer the best.

    If you're STILL not happy it's time to get serious! There are cams and big bore kits and oh my!

    Be thankful you have this level of aftermarket support, heh.

    Comment


      #3
      Thanks alot for the info mate im going to get to work, the bike runs fine with the 4-1 on but i need to rejet and get the carbs balanced but yeah im going for individual filters and will ahve to rejet again but im doing that next year



      Originally posted by Commodus View Post
      At about this time you'll be thinking, "man, this suspension sucks" and you'll be right.
      lol yeah i been thinking that for a long time now the rear is far too soft and a pain in the ass the front i was thinking of progressive springs

      Originally posted by Commodus View Post
      If you're STILL not happy it's time to get serious! There are cams and big bore kits and oh my!
      tell me more, what can i do with the cams?

      thanks for info mate
      Last edited by Guest; 10-01-2006, 10:53 AM.

      Comment


        #4
        Originally posted by Commodus View Post
        Ah, you picked a great bike to start with.

        STEP ONE: Make sure the bike works! Check, adjust, lube everything. No point in trying to tune your carburetion if your ignition is weak, for example.

        First, pick a good 4-1. I don't have any experience with Harris, but I heard they make good stuff. If not them, buy a V&H pipe:



        Then, make the carbs work. Decide if you want to ditch the airbox (I always do) and go from there. If you go pods, buy the K&Ns. I don't know if they make a jet kit for your year, but if they do it'll make jetting a whole lot easier. If they don't, you may want to keep the airbox.

        Then ditch the points and coils, go with a Dyna S ignition:



        and coils:



        At about this time you'll be thinking, "man, this suspension sucks" and you'll be right.

        Here:

        Fitting & Adjustment Instructions for Ikon Stereodampers Type 7610 and 7614.For further Shock Absorber Specifications please see view


        for the rear,

        Here:



        for the front.

        Most people go with SS brake lines, they help a little. Mostly they look bitchin:

        http://www.galferusa.com/MOTO.html I like Galfer the best.

        If you're STILL not happy it's time to get serious! There are cams and big bore kits and oh my!

        Be thankful you have this level of aftermarket support, heh.

        wtg - gr8 post m8

        kool input = GSR


        cheers

        Phark

        Comment


          #5
          Originally posted by pharkmeh
          wtg - gr8 post m8

          kool input = GSR


          cheers

          Phark
          yeah is a great post
          one more question
          what about brakes cos mine suck
          Last edited by Guest; 10-01-2006, 11:02 AM.

          Comment


            #6
            Hey, glad it helped.

            Brakes...well, there are a lot of options, it depends how rich you are and how handy you are. Again, though, make sure the brakes work OK first! You might find that a properly set up pair of GS calipers work OK for your purposes! But if not...

            If you're rich, there are a number of companies that will sell you a nice pair of calipers made to any specs you want.

            Realistically, though, you're probably not gunna spend that kind of money on an old GS. So, what virtually everyone does is find a set of modern calipers and graft 'em on. If you're sticking with the stock forks you're also probably sticking with bias play rubber, so you don't have to get too crazy. Pretty much any caliper on any sporting bike from 1985 on will give you all the braking you need, and because most of the specials-builders are looking for the really modern stuff, they're cheap to buy too. But, none of them are going to just bolt on, so you're going to have to fab up a bracket. If you don't have the skills for it, any fabricator or welding shop can do it for you for not much money.

            Of course, none of that matters much if you keep the stock master cylinder, cuz it's terrible! So, the same time you buy the calipers, make sure you get the cylinder along with! Rebuild everything when you get them, you don't want to trust your life to "well, they worked when I took them off the bike" !!!

            As for cams:


            - buy a set that doesn't require any other mods, remember it IS an old bike! Head mods will start to run you a lot of money! Use either 70-051 or 70-061, depending on whether you go the big bore route.

            Make it bigger!!! (note that this one mod is probably the best or second best [I'm a big fan of those Mikuni RSs] 'bang for the buck' mods here - no replacement for displacement, and all that )


            (pdf file, take note)

            However, if you wanna go that far, you'll also want to ditch the stock carburetion, cuz it sucks too! OK, not really, but you'll get some great gains with a rack of Mikuni RS smoothbores:

            http://www.sudco.com/ - for some reason I can't link directly to the RS Application page, but they sell a set of RS34's that work on the 750s.

            Be sure and call 'em first, though, I've never used a set with the earlier 2V bikes. The greatest thing about this mod is you won't have any "er...hey guys, i have this weird flat spot, and sometimes one cylinder dies..." kinds problems that are SO prevalent with these old bikes, and very often caused by worn or gummed up carbs. Do a quick search right here if you wanna know how annoying that can be!!! ](*,)

            I would definitely recommend buying the carbs BEFORE the cams and big bore kit. You may find that you are perfectly happy with the power output after the ignition/intake/exhaust mods, especially if you bolt on the smoothbores - they make a big difference!

            Be aware, the carbs cost $800!!! That's a lot!!! A much cheaper option is a set of "semi-cvs" from a later model, perhaps a GSXR 600 of 750 for example. You can find these all over ebay, $200 seems to be the average price. Try and get one from an auction that lists the mileage of the donor bike, carbs CAN wear out, though at quite high mileage - anything under 50K is probably fine, though buy the loweset mileage set you can, of course. If you go this route, buy a rebuild kit at the same time, and rip them apart and completely rebuild them - just IMHO, of course, but I've found that if you start with a 'known' set of carbs it greatly simplifies the troubleshooting process later!

            Make sure you use a 'push-pull' throttle if you do this, there is quite a tragic post in Katanaman's ICBM Katana thread (which is actually really fantastic, and contains some of this information and a lot more besides) about what can happen if you don't! You can buy them very cheaply from eBay all the time, seems those GSXRs crash a lot!

            Good luck, and make sure you set a budget first! That will make a lot of your decisions for you, and help guide the project!

            After that, of course, you can start looking into modern forks and wheels and rubber! But that's a whole other ballgame!

            Comment


              #7
              Here's another option.
              Take a look in appearance mod section also

              Keith
              -------------------------------------------
              1980 GS1000S, blue and white
              2015Triumph Trophy SE

              Ever notice you never see a motorcycle parked in front of a psychiatrist office?

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