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Welcome to my little Kawasaki KZ750 Twin info site.

To get started, click on any of the categories at the right side of the page or the links at the top of the page.  Or if you need to find something more specific (like “service manuals”), use the search at the top right.

Enjoy!  …and thanks for stopping by…

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236 Comments

  1. Biquetoast

    @Dave –
    I wish I knew… I’m betting the ’83 will work, but probably not anything else. Anybody else got an idea?
    -‘Toast

  2. Carlos

    @Dave
    the air box for the 78, 79, and 1980 750-G1 model of the twin might fit in the actual space in the CSR, but the boots are a different size, since the earlier models hav different carburetors. the side covers for the G1 will probably fit. I don’t know about the 83 models, but it’s definitely worth a shot.
    @biquetoast
    tomorrow I’ll tension the drive chain a little more than it is now and see if that fixes the vibrating. I definitely haven’t heard any noises from the chain suggesting it’s loose but it’s def a possibility! I’ll letcha know my findings tomorrow.

  3. Biquetoast

    @Carlos –
    Just to be clear… I didn’t mean to suggest it’s *loose*, it actually might be fine as far as tension goes. On my 2 750’s, they both do this, but one more than the other. I have found that it has to do with wheel *alignment*, and certain harmonics that come from the engine at certain RPMs and chain tension. Again, I don’t know if this is what’s happening to you, but your description sounds so much like it. A couple things.. If you feel that unusual vibration starting to form, does it go away if you back off the throttle a tad? Have you ever looked down at your chain when the unusual vibration starts to occur to see if the bottom if flapping wildly side-to-side? I asked about this a couple times in the forums in the past, but most folks thought I was crazy… And who knows, as Billy Joel once said, “…You may be right…” 😉
    -Toast

  4. Carlos

    @biquetoast
    actually, I had the wheels trued before I painted them, so it probably isn’t that. I measured the chain as per the service manual and I got a reading of 320mm, which is about 2mm above the standard limit. I assume the person before me hadn’t bothered to tension the chain accordingly, so I did that this morning, and *most* of the vibration I was describing went away. hell yeah!

  5. Carlos

    @biquetoast and everyone else who might be interested
    so I changed the oil in my motorcycle not too long ago and it started smoking. I performed a more scientific compression test this time and I got 145 psi in the left cylinder and 170 in the right cylinder. Not good. I also suspect the valve seals are trashed and need to be replaced. I went on eBay and did a little snooping and found this store who’s selling brand new ART pistons and rings for 40 dollars a pop. ART is the company who made almost all of the original pistons for kawasaki, so this an incredible deal. I also found brand new Viton valve seals for 15 plus free shipping. The valve seals for the twins are a joke to find because kawasaki apparently decided to use unique ones for these bikes and the same ones for every other goddamn model. Anyway, total is 108 dollars for everything, but I’m still talking to the seller to give me a break on shipping.
    As far as gasket go, I make them all myself. We’ll see about the head gaskets.

    Thought y’all would like to know if anyone is performing a top end rebuild.
    Cheers

  6. Johnnyblades

    How do you get the blind cap plugs out of the four locations of the headbolts? Manual say use one of the cap bolts from the rollers that lock down the cam I tried that but still can’t pull them out. any suggestions would help.

    Johnnyblades

  7. Carlos

    @johnnyblades @biquetoast
    funnily enough, I was about to tell those who come on here how my rebuild went. all well; ~155 psi in each cylinder and running like a rocket. to get those blind caps off you have to use your imagination a bit. three of mine came out easily, one did not. what I did was leave the camshaft caps on the head with the bolts on, place a towel or some such thing over them, and use it as a leverage point with a robogrip (if you have one, if not, something similar) to pull them off. moving the cap around in a circular motion helps. if they won’t come off, I suggest spraying some PB blaster on them and leaving it for a while so it gets past the o-ring. unfortunately the age of the rubber and the heat of the engine create a pretty tight seal. obvs you’ll want to replace the rings when you reinstall the caps.

    as an aside, be careful with the chain guide if you’re removing the cylinder block. major PITA to remove and install, so make sure you have it on the right way. good luck.

  8. Biquetoast

    @Carlos –
    Thanks for pitching in! I’m also a fan of PB Blaster.
    @Johnnyblades –
    I hope that helps…
    -‘Toast

  9. Johnnyblades

    Thanks for the advice I will check out the robogrip I will try to get some imagination and patience this one blindcap is something else
    thanks again.
    Johnnyblades

  10. Michael

    Hello.

    I have a 1980 KZ 750 G LTD. I need to order a new stator and regulator rectifier. I can only find the parts online for the KZ 750 H LTD model. Do you know if they are the same parts for the two models?

    Also what are the main differences between the two models?

    Thank you!

  11. Biquetoast

    @Michael –

    If my memory serves, the “H” is the four-cyl model that debuted in 1981. What you need for the 78-80 models is likely to be listed as the “750B” or something. Just make sure you don’t get it for the first two years, the ’76 and the ’77, because they had different electrical systems. It changed in ’78, and remained at least through your ’80 (I can’t recall if it stayed the same for the ’82 – ’84).

    -‘Toast

  12. Carlos

    @michael
    the regulator/rectifier on the G is the same as the 1982 M, if memory serves me right. http://www.amazon.com/gp/aw/d/B00KOR2JKS/ref=mp_s_a_1_2?qid=1407269434&sr=8-2
    I had to replace mine and I used this. no complaints. also, are you sure you have to replace the stator? those things are pretty hardcore. did you run the AC output test?

    anyway, I came on here to ask about carb tuning. do any of y’all know about tuning the pilot air screw? my idle’s a little erratic, and I think the air screw is too lean. is it in for leaner and out for richer?

  13. Michael G

    Where or what can I get a block off for the Tach on Kz750g?

  14. Paul E

    Hey guys! I just got my hands on a “79 KZ750. I rescued it from my dad’s garage, and it needs a lot of love before it’ll see the streets again. Who is still around on this page? I might be looking to lean on some of you guys for mechanical advice. Thanks! – Paul

  15. Martin Schetter

    Waht happened to the kawasaki twin owners forum. Not available any more??????
    Martin

  16. Biquetoast

    @Martin-
    Hmm.. yeah, seems to be down, but the domain still exists. The URL last time I checked was: http://kz400.createforumhosting.com/ but it may have changed…?

  17. Biquetoast

    @Paul –
    I’m here, I’m glad to help how/when I can…

  18. Dwight

    The whole of createforumhosting.com is down. I looked it up and their domain registry expires next month. Doesn’t look good.

    @Biquetoast and others:
    I have a 1983 KZ750K1 (Belt drive). I finally tracked down a center stand but I can’t find a affordable shaft for it. Would anyone have access to the dimensions so I could have one manufactured?

    Thanks!

  19. Martin Schetter

    Please get in contact by mail

    Martin

  20. Kawavorka

    I just noticed the Twins Forum is down. Does someone have it archived? Who was running it? Can it be moved to another server? I need my Twins Forum!!!!!

  21. damien

    Hi all,
    Sad the old forummhas gone, it and the people posting were a great help to me over the years.

    I do have a quetion now if any would like to suggest infomatiom.mi have been chasing a gremlin in my bike (kz750 b4 twin, stock). It runs fine but now when it rains it always runs rough, seems like its runs on one cylinder or bogs down, backfires a bit. If it does this and I give it a few good twists of the throttle and a good rev it will even out but then once I let of a bit the rough running returns? I figure I am looking for a bad earth or short some where that the water is getting to? Im also wondering if this sounds like a bad coil? I have done a check of the loom as best I could and replacesd points condenser and cleaned and put a new carb kit in. Any suggestions appreciated. Thanks

  22. Jay

    hello,
    I have a 1977 KZ740 twin, that needs an new motor. I found a Salvage Yard, that has one for sells and turns over. Any advice before buying motor?

    thanks

  23. Fernando

    I just bought a 1980 KZ 750G twin LTD, everything is there except that where it was stored rats had their way with the wiring harness. Does anyone know where I could purchase another one or at least find the diagram to rebuild what’s left of it or a totally new one?

  24. Dusty

    I’ve got a 1980 KZ750t LTD (so, the twin or G model as I understand it). I recently picked up a mainstand off eBay, that I now suspect was from the four-cyclinder E model, as there doesn’t seem any easy way to mount it to my bike. Anyone know if this is possible or how to go about it? Thanks in advance.

  25. Biquetoast (Post author)

    @ Fernando –
    The wiring diagram is available right form this site from the reference section. In fact I think I have a couple manual versions, at least one of which should include the ’80 G model.
    – ‘Toast

  26. Biquetoast (Post author)

    @ Dusty –
    Well, you got me there. I have no idea if and how the stand from the four cylinder bike would fit the twin. They are completely different bikes. Not saying it can’t be done, but I just don’t know.
    – ‘Toast

  27. Dusty

    Toast – thanks for the quick response. I didn’t mean to bring a stumper like that right out of the gate. Of course the auction I bought from only said a 1980 KZ750… didn’t specify twin or four, so I just figured that part of the frame was the same… obviously not. I wonder if anyone has close-up pics of where the centerstand mounts on a four? I can’t seem to find on anywhere on the webz.

  28. Vince

    Any chance we can get the forum opened up again?

  29. V. Ryan aka antiq

    biquetoast please email me. I want to get a forum going for these bikes. I miss the old forum and would appreciate your help.

  30. Lonesome Twin

    Biquey!! You’re still around, really good to see. Me and Kaptain are working hard to set up an all-singing all-dancing 750Twin site, will post here when it’s ready. Roll on, old friend.

  31. Adam

    Hello,

    I am the proud new owner of a 76 KZ750. You can imagine my excitement to find this site. She runs okay and I am hoping to keep it that way until winter when I can do some real tinkering. In the meantime, I would really love to get some storage capacity so I can take it camping.

    I was wondering if anyone has found a tail luggage rack and side mounting racks that work. I would love to have hard boxes on the sides, but will go with soft saddlebags if that’s all that works. I have found rear luggage racks on eBay for the 81. Does anyone know if they will mount on my 76?

    Thanks!

  32. Biquetoast (Post author)

    @Adam
    Welcome to the world of the KZ750 Twin! This site is just little ol’ me keeping track of stuff, and occasionally people stop by and reply. If you want a lot of good help with lots of helpers, you should try KZRider.com and the like. But I hope you love your KZ as much as I love mine. About the rack, warning… There WAS NOT a 1981 KZ750 TWIN, but there WAS a 1981 KZ750 FOUR-cyl., that had no relationship whatsoever to the twin. The twin were 76-80, then 82-84. The 76 shares almost all with 77, and quite a lot with 78-79, and still less but much with 80. From 82 it was redisigned and still shares similar engine parts, but it gets much less alike as you might imagine. I hope that gets you started…
    ‘Toast

  33. John W. Mueller

    Hello to all. I have a 1980 KZ750 G1 for sale. All original plus new OEM replacement parts that I’ve purchased. Currently disassembled (engine intact), for a clean-up and restoration. Tank, side covers and tail piece are candy apple red w/ gold stripes.

    Write for info/details.

  34. phil17

    Hello to all I am French and my English is a little poor so be tolerable please. I have a Kawa 750 B2 1978 for me and I think 1977 for American people (VIN 24462)I must change my front brakes and don’t know exactly the parts I must buy so I need some help. For the front brake there are 3 parts I need The dust seald rubber with his ring and the ring piston seal but I only find the dust seald rubber (43054-003) without the metal ring ??? and the rubber ring piston (43049-002)For the front master cylinder I need the repair master set-master cylinder (43073-001) but I don’t find the reference of rubber seald which is before the stopper-boots (43025-001)Can somebody help me ????
    Thanks

  35. John

    Hello, I have a 1978 kz750 b3, she starts and runs very strong through all gears and rpms until I get to 5th gear on the highway. I will hit 5th gear and open the throttle to advance to desired highway speed which is usually around 70-75 mph. Just as I approach 70 mph around 6000 to 6500 rpm the engine bogs down, I mean just cuts out like I just ran out of fuel unless I completely let off the throttle, when I do (let off the throttle) it takes about a second the engine cranks right back and I can maintain around 60 to 65 mph for as long as I want as long as I don’t roll the throttle back too far. This is very consistent as it will repeat every time I roll that throttle back too far. If you can give me any advice on what the problem is I would greatly appreciate it. Thank you

  36. Biquetoast (Post author)

    @John –
    The first thing I’d do is see if you can try to determine if the problem is caused by 1.) carburetor stage, 2.) engine RPM, 3.) fuel flow (or other). For item 1, you’re well into the carb “main” only stage, so I don’t think it’s a jet problem but it could be clogs or fuel flow in the carb limiting you at that rate. You say it runs, but does it run *perfect* at all other gears/rpm? Also, you’re pretty high up in RPM at that point, so I don’t think it’s the advancer, but if timing is off it can reveal itself at that RPM.. you might want to check that. And I’m not sure I suspect coil/spark, because that usually reveals itself at lower speed. At the moment, I’m thinking it’s item 3, fuel flow. There’s a few places to start… try running with your gas cap pooped open, to make sure there’s sufficient air-flow *into* the tank to replace the fuel that exits the tank at that RPM. Make sure there’s no clogs in the petcock, filters, etc. Do you ever notice leanness at that RPM? You can tell if you have white or light-colored plugs if you ever do a “plug chop” from that RPM.
    I hope that helps a bit, good luck out there… -‘Toast

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