New to me GT750 project!

Discussion in '2 smokers' started by LasseNC, Mar 21, 2014.

  1. LasseNC

    LasseNC XSessive!

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    #21
  2. LasseNC

    LasseNC XSessive!

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    I think so :)
    #22
  3. Zuber

    Zuber Zoob

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    My first time in the 2 smoke thread...

    I worked at a Suzuki shop when these were new. Fantastic motor, Suzuki was way ahead of the others. The frame, not so much. Minimum, replace the steering head bearings with tapered. Replace the plastic swingarm bushings with alloy, bronze, steel and grease them. Brace up the steering head and swingarm, run a brace from steering to swingarm.

    The early models were hotter, they had higher compression and slide carbs. The CV carbs and the lower compression models, esp. the 75-76, were a compromise to make them run cleaner and not backfire through the airfilter. If you run the CV's, keep the air box, or as much of it as possible. The airbox had plenty of flow. But, ditch the CV's and get three slide carbs, about 34mm.

    We did a big job for a customer where we raised the ports 5 mm on his 73 buffalo. You can't just carve this out or you'll get into the water jacket. So, we machined 4mm from the top of the cylinder and then made a 3 to 4 mm spacer for the cylinder base. It raised all the ports and raised the compression a lot. Carved the ports higher and lower, cleaned up the transfers. No electronic ignition back then, so the hot set-up was K-Mart auto coils hose clamped to the front down tube and points. 36 mm Mikuni's with pods, three expansion chambers (Jardine I think). Ran great, pulled from 3000 on up. The sound was very addictive. Maybe 25 mpg.

    Would be great to stuff this motor into a modern sportbike chassis, if you could get the crank high enough to not drag.
    #23
  4. LasseNC

    LasseNC XSessive!

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    I'm running tapered bearings in the head stock and the swingarm. Also got the airfilterbox as suggested. Other carburettors is too much hassle I think.

    Sent from my RM-914_eu_denmark_410 using Tapatalk
    #24
  5. Krasniewski

    Krasniewski I don't ride much.

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    Lookin' good! I've been gunning for a sweet two smoke project - this makes me pretty jealous!

    #25
  6. Duck_Pilot

    Duck_Pilot Retired Roadracer

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    A co-worker of mine has one - mostly complete - that he'll sell cheap. Most likely a '73 or '74 by the OEM equipment. It was slated for 'resto-mod' by the past owner, and there's some good GS-750 parts there to use. If you PM me your contact info, I'll forward it for you.
    #26
  7. Krasniewski

    Krasniewski I don't ride much.

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    PM sent.

    :)


    #27
  8. drdfblackm

    drdfblackm VeeFeer

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    I am picking up the little brother tomorrow. 1972 GT 380 J. Very excited about it!!!!:clap:clap
    #28
  9. FastHydra

    FastHydra Adventurer

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    Great smoker for touring. Get rid of that 3-1 shit, all that is doing is decimating your performance. Two stroke exhaust need expansions for sound reverb/back pressure to push unburned fuel mixture back into the cylinder for the next combustion.

    I like to think I'm a multi cylinder 2 stroke guru :p I've been playing with them since I was old enough to watch my dad do it. I have a formula if you want it or a program that you just plug in current specs and desired power output and power band range and it gives you the precise measurements for every cone to produce the desired results.

    I tried watching cafe racer tv a few times. Every time they did 2 strokes they put pods and cut off straight pipes, then cried when they couldn't get it to run right(or at all)... If I drank I'd have thrown a beer at the TV but I don't and I'd never throw Mary lol.

    Good luck with the Buffalo.

    P.S. Pods look cool but the 3-1 K&N boot filter are hands down the best performers for any application (I'm more familiar with twins but the principles are the same)
    #29
  10. Duck_Pilot

    Duck_Pilot Retired Roadracer

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    If he's keeping the CV carbs, I most certainly agree. If he's switching to a set of slide-throttle units, individual filters are fine.
    #30
  11. Spikester300

    Spikester300 Roll Tide!

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    I think you got this backwards, the early ones were low compression and the '75 on had thin head gaskets and a higher compression head with different porting than pre 75 models.:freaky
    #31
  12. FastHydra

    FastHydra Adventurer

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    Yes they would be fine but even with flats the K&N will give better performance. Air pressure on these 2 strokes is everything. Run em just a little rich due to pressure difference on cylinder X and they are dogs, but find the sweet spot and hold on!

    On a water buffalo i would leave it stock(except pipes, filter and jets maybe) and use as a touring/adv they are comfortable and SUPER reliable I've personally seen 40k+ on original cylinders.
    #32
  13. LasseNC

    LasseNC XSessive!

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  14. LasseNC

    LasseNC XSessive!

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  15. Leo.G

    Leo.G Is still learning

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    SWEEEETTT!:clap
    #35
  16. LasseNC

    LasseNC XSessive!

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    I will take new pictures tomorrow, when the sun is back.

    I'm aaaaalmost there!
    #36
  17. LasseNC

    LasseNC XSessive!

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    #37
  18. RedRocket

    RedRocket Yeah! I want Cheesy Poofs

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    Bump for a smoke cloud
    #38
  19. LasseNC

    LasseNC XSessive!

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    The bike is as the last picture, more or less. I've added a headlight and a rev. counter.

    I need things like a rearchain and a battery, then I should be waiting :)

    I'm just waiting for summer now :)
    #39
  20. RedRocket

    RedRocket Yeah! I want Cheesy Poofs

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    I rode a modded GT750 back when I was about 17. I remember it being fast enough to scare me.
    #40