1982 Kawi GPz-550 Cafe Build

Discussion in 'Some Assembly Required' started by HuckIt, Aug 21, 2021.

  1. HuckIt

    HuckIt Been here awhile

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    Picked up a 1982 GPz 550 project off OfferUp today. It's roughly 50-70% complete as the previous owner powdercoated the frame and wheels and had the top end done with a mild port (so I'm told). He also put new tires on it and had the tank and fender painted. All good stuff, not the exact color schemes I would have chosen - but they look good.

    PXL_20210821_172432137.jpg

    The bike looks very complete, and it basically is - guy purchased a lot of nice parts for it, billet rear sets, new rear rotor, chain and sprockets, braided brake lines, 27mm flatside carbs, new speedo and tach. He also swapped in an 84' wiring harness for some reason. I'm expecting the wiring to be the biggest challenge as everything still needs to be wired up including the new gages, switches, etc. And who knows if this new harness is any good. Hell, I don't even know if the motor is any good. But the guy seemed honest enough, we knew a few of the same "motorcycle people" in town. Small world actually - the same guy who painted this bike painted my 96' Ducati 900SS project I did a few years ago; guy does great work.

    Here's my last project:
    IMG_20180408_172841.jpg
    The GPz came with a decent stash of spare parts so I should be able to piece together whatever I need on the electrical.
    PXL_20210821_171344724.jpg

    I'm not a huge cafe racer fan, I generally like the look but I'm more of a race bike guy (as you can see from my Ducati project). So my plan is to get this bike going and then running really good, the carbs will need to be jetted/synced and I need to get a header. Then tackle the suspension and make it handle as good as possible for an old bike. Then just ride it for a bit and see if I like it and what needs to be adjusted.

    Anyways, enough rambling. Only project today was making a work stand so I can easily reach everything and still get the cars into the garage.
    PXL_20210821_193536271.jpg

    Hopefully start making some progress tomorrow and will try and keep this thread updated on the progress.

    Major tasks:
    Wiring...wiring....wiring
    Make linkage for rear brake
    Make linkage for shift lever
    Find new rear brake line (current one is too short)
    Find tach cable and install
    Find throttle cables and install
    Fab seat pan
    Fab rear taillight mount
    Fab battery box
    Find brake reservoirs, fill and bleed
    Drill/tap new 520 front sprocket for retainer plate
    Run fuel and vacuum lines
    Install fuel sending unit in tank

    I'm sure there is a bunch I'm not thinking about off the top of my head....Oh yeah - refill garage fridge with beer!
    #1
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  2. motocopter

    motocopter Long timer

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    Cool!

    Will follow to see how this goes for you.

    I bought a new '83 550GPz back in the day from Kawasaki of Denver. Added the Canadian jet needles, Kerker racing exhaust, and a Moriwaki 600cc 11:1 kit.
    #2
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  3. Gedrog

    Gedrog 1000 mile stare a 1000 stories to tell

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    Classic beasty in my youth we had 500cc club and the GPZ was very popular. Cheap as chips guys converted them into all sorts choppers, cafe racers, etc.
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  4. HuckIt

    HuckIt Been here awhile

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    Awesome! I bet those upgraded really woke it up
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  5. motocopter

    motocopter Long timer

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    Did some road racing with the MRRA guys in '84. One heat race I got the holeshot from the pole. Came out of the first corner in about tenth! Some how my left foot came off the peg, too high of a gear, and took a bit to get going. :lol3
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  6. HuckIt

    HuckIt Been here awhile

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    Made some progress this morning on the shifter side rear-set. Was fairly straight forward once I got the 'lever' in the right position where everything looked like it would clear. Also had to cut the stock rod end off the donor shaft adaptor as I couldn't seem to get the c-clip out.
    PXL_20210822_163359114.jpg

    Once the position was right just needed to cut the threaded rod, chase the threads and then cut the sleeve to length.
    PXL_20210822_165749363.jpg

    Moved over to the brake lever and couldn't see a good way to use the stock lever to connect to, has a weird bend in it that goes the wrong way. I decided I need to source a steel lever that will give me more options with welding on a spacer or change the shape. Found one on eBay off a Kawasaki KZ1000 that looks like it may work, waiting on the seller to measure the shaft diameter to confirm. After looking at it again, if that lever won't work I'm going to give the stock one a try with my hacksaw/grinding skills...
    PXL_20210822_171302693.jpg

    Finally, messed with the seat/tail section a bit. Had to move the pan holding the various electronic pieces below the current mount to get everything to clear but the seat does sit down nice now and the bumbers line up with the frame rails. Decided I'm going to add a rear hoop so I have something to mount the taillight to, really wish this had been done before powercoat but what are you going to do.
    PXL_20210822_173904189.jpg
    PXL_20210822_173910730.jpg
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  7. VX Rider

    VX Rider Long timer

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    One could make the hoop with plugs welded with nuts welded so it could be bolted on from the inside of the frame
    with two bolts each side. then the hoop could be powder coated painted after fabrication.
    And only a couple of holes would need to be drilled in the already coated frame.

    Napkin Sketch for you...

    upload_2021-8-22_14-54-32.png
    #7
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  8. 3legs

    3legs Real men ride sidecars Supporter

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    Be interesting to see the final weight. See how much weight was lost.
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  9. Nathan_66

    Nathan_66 Been here awhile

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    izzat KERKER meg in the box? The KERKER'd gpzs were big back in the day in the north east!!!

    My parents said 'NO!' when I begged for a gpz when they first came out because I'd already crashed big on a dirtbike a few years earlier lol...

    Fun project and good stuff!!!
    #9
  10. HuckIt

    HuckIt Been here awhile

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    That's a good idea - I like it. I was also kicking around sanding down to metal about 1" from the end on each side, welding the loop on, and then painting it black from the stripped portion back. Could do essentially the same thing with your idea, just need to decide if I want to mess with welding I guess. I actually think the loop in black would look good and may break up all the red on the frame. I already think the frame color is going to overwhelm the overall look, so at a minimum I'm going to clean up both engine side covers really well and then paint them silver(ish).

    Thanks for the sketch :beer
    #10
  11. HuckIt

    HuckIt Been here awhile

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    I'm curious too, when I picked it up I used my hitch hauler (Cycle Gear Trackside) and I was a bit concerned with putting the bike on it based on the published dry weight (460 lbs) versus the hitch rating (500 lbs). Before the flames start (:shoot), I would never go near that weight, and I have reinforced my hauler quite a bit by welding in additional bracing, and I had an easy 20 mile drive home on smooth backroads....I would say the bike when I picked it up was easily under 400 lbs, felt like wheeling around a modern 600cc sport bike. When finished, it would be great to see it under 400 but that steel frame may push it over.
    #11
  12. HuckIt

    HuckIt Been here awhile

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    Yep, that is the one - neighbors should love it especially after I merry it to a good 4:1 header!

    The GPz's were just my time, but I did take my drivers test on a borrowed Ex500 in 1990 when I turned 16! No way my parents were letting me get a street bike back then either, so my XL250 pulled double duty when no one was looking.
    #12
  13. motocopter

    motocopter Long timer

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    How about some sleeves inside the openings in the frame tubes at the end? Then use the same diameter tubing for the tail light hoop. Rivet or bolt the joiner sleeves to the frame and tail light hoop.
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  14. VX Rider

    VX Rider Long timer

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    If you do what I described, you can paint the hoop any color you want.
    The red on the frame need not be touched, just place several layers of blue painters tape
    where you drill the holes to bolt the hoop on.
    If you us solid slugs to join the pieces it would be fairly strong.
    If you used tubing you could run your tail light wires inside the frame.
    #14
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  15. HuckIt

    HuckIt Been here awhile

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    Looking at it closer I think I'll have to weld it, if I use bushings on the ID it will need at least an inch or so of straight section for the sleeve to slide in and I think that will make the hoop stick out too far. I have a hoop on order so I'll take a closer look later this week when it shows..
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  16. VX Rider

    VX Rider Long timer

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    INSIDE...think inside the frame tubes then you wont see the extra length
    upload_2021-8-22_19-39-1.png
    #16
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  17. HuckIt

    HuckIt Been here awhile

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    Got the brake linkage worked out with the new rearsets today, ended up making due with cutting down and tapping the old aluminum brake lever.

    Brake Adaptor.JPG

    With the lever end reversed like I had to use it it sticks out proud from the shaft and just looked ugly. Cleaned it up and shaved down the end the best I could to get it to look OK.

    PXL_20210823_043702239.jpg

    After this we (recruited my younger son to help) verified all motor mount bolts were tight (they weren't) and the tore everything down. I still need to rebuild the forks and I think I'm going to either paint or have all the small pieces/brackets powdercoated black so everything looks nice. Seems a shame to have such a nice frame and paint job but have a 1982 patina on everything else.

    PXL_20210824_035533353.MP.jpg
    #17
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  18. motocopter

    motocopter Long timer

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    Front wheel sizes were interesting in those days. 19 inch fronts were popular and then in '84 the 16 inch front wheels came standard on the new Ninja 900. Honda VFR's. Suzuki GS's and Katana too.
    #18
  19. HuckIt

    HuckIt Been here awhile

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    Interesting all the changes and now things seem to have settled into everything at 17-inch for sport bikes for the last nearly 30 years. I guess I'm considering this a sport bike..:hmmmmm
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  20. HuckIt

    HuckIt Been here awhile

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    Last night was spent mostly trying to track down caliper and fork rebuild parts, finally got what I needed on order from MotoSport and good old Amazon...

    Tonight we stripped down the calipers and pulled the remaining side covers. Also pulled the rear shock so I can get the spring powdercoated (or put on a new one, TBD), but with the preload backed all the way out I still couldn't compress it enough to get the retaining clip out. ugh. Will have to find a spring compressor or maybe take it to a buddies house that has a press we can use to rig up a way to compress it on.

    Parts are all boxed up and ready to get sand blasted and painted/powder coated short of getting the spring out of the shock.

    I'm sure that will be 1-2 weeks assuming they are as busy as everywhere else.

    I had ordered the rear frame hoop and the one I ordered (230mm outside to outside and 25.4mm diameter) showed up and was 230mm and 21mm diameter....Crapola, ordered a different one of eBay that will hopefully be as advertised. With any luck maybe it will show up by the weekend along with the fork seals and I can get both done.

    PXL_20210826_033707921.jpg

    Attached Files:

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