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1981 Kaw GPZ 550

Discussion in 'Other Motorcycles' started by Timbox, Aug 22, 2024.

  1. Timbox

    Timbox Well-Known Member

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    Well my friend let me know that a GPZ 550 came into the scrapyard. Went over to take a look at it. It was in okay shape but not really.
    [​IMG]GPZ 550 by Tim Brown, on Flickr

    I had to see if I was going to part it out (still might) or if it wanted to run.
    Checked the spark, only #4 was showing spark. Cleaned all the contracts on the coils, smashed down each coil lead a little. Cut off a little spark plug wire on each end and cleaned the plug caps. Have it a shot of carb cleaner and yes it ran.

    Pulled the carbs off and well, we have another bike that has the starting ckt jet in the bowls. Nice green fuel in the #1 and a little in #2 as they seem to be on all bikes left for yrs on their side stand. Always put them on the center stand for long term storage.
    [​IMG]GPZ 550 Carbs by Tim Brown, on Flickr

    Took me a few hrs to clean them and give the bike a try. The fuel tank is I think shot, I mean the amount of rust and wheep holes are bad. But put AUX tank on and this bike fired right up, with a jump across the solenoid as the starter swx does not work.

    Now, do I turn this into a winter project and bring it back to life or just part it out. Oh, ya, the oil cooler also has a good leak in it. Some parts are not too expensive but they all add up. Would need a bonded title too. Something to think about as I tinker a little more with it.
     
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  2. chris123

    chris123 Active Member

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    Very nice!

    Title issues always scare me away, but if the price is right I could see it being roadworthy.
     
  3. Aurel

    Aurel Member

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    Here in Texas a bonded title is super easy to get, as long as vin is clear, $200 and you get it.

    On the other hand, prices and availability of bikes here are really bad... I can still get a great deal once a year or so, but when I'm looking at Philadelphia/NY on marketplace, I'm salivating

    Good find tho @Timbox ! Could be a nice project
     
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  4. Timbox

    Timbox Well-Known Member

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    Found a few things wrong with it. The oil cooler leaks, have bypassed the cooler for now. Just ran a tube from one side to the other as I put a fan on the bike when it runs. Cleaned up and installed the PODs, for now. Just to see if the bike is worth the effort. Ran through the gears on the table while the bike was running. Bike does run well, I was surprised to say the least at how well it runs.

    Now comes the fun part of the electrics and troubleshooting. Started with the starter ckt and moving on from there. I have found lots of contact corrosion and cold broken solder joints. Always fun trying to solder them little wires into those very small contacts.

    [​IMG]455959085_1896757954155972_6270523988108341492_n by Tim Brown, on Flickr

    First, the starter button was not making contact. Then the second pic is of the power to the starter ckt the red wire came off the contact. That was fun getting back on.
    [​IMG]456694312_1621006548513651_3233158243744644067_n by Tim Brown, on Flickr

    I am now working on the turn signals, looks like there are two separate turn ckts on the bike. It has two flash relays on it, so the grounding is giving me issues. I will have to order a manual as the wiring was all buggered up. Cutting and replacing crimp wires as I go.
     
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  5. Timbox

    Timbox Well-Known Member

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    Well, keeps getting better. Good thing this bike was cheap, and the motor is good. While troubleshooting the turn signals, I now have power on grounds. Yes, something in the instrument cluster is doing it. Unplugged that and the short to power on the ground goes away.

    Looking at a minimal wiring concept now, I think. I would be able to use my phone as a GPS speedo if nothing else. I will look on ebay to see if there is a good instrument cluster on there but I would guess not for the price I want to pay. Stripping down the wiring harness to just make it have headlights, tail, bake and turns along with the ignition and charging system. I do think most of those systems are separate wiring for the most part. Just something I am thinking about doing.
     
  6. Timbox

    Timbox Well-Known Member

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    Sure enough, stripped off the speedo gauge and removed the wiring to use in the future. Sure enough, plugged all connectors back in and did some testing with the Power Probe and all the lights work as they should. Tail light even started to work along with the brake light.

    So just keep after the issues and troubleshoot it down to a component and go from there. Some of you might think I should have found the short in the gauge, nope, part too old and just would never trust it again.

    [​IMG]455304668_494764940173414_7690479415017190332_n by Tim Brown, on Flickr
    That was the issues, someplace in there will all them wires a 12V found a ground wire and made all the lights do weird things.

    [​IMG]456882440_1485444002857421_5601399258530818284_n by Tim Brown, on Flickr
    Rigged up the lights to make sure the ckt had good resistance, looks ugly but works.

    [​IMG]456081594_480773428075332_5740483440834780339_n by Tim Brown, on Flickr
    I know she is ugly, but lights work and the bike starts right up and runs. I did check the trans the other day, ran it through all the gears while it was running. Chain is ruff but will work for now. Tires are dry rot, but the rear is now holding air. Both tires were leaking air around the bead area, lots of soap, water and a little more air took care of the rear, still have to work on the front.

    Seat, oil cooler, front brake lever and a lot of tlc with brakes and the rest of the safety stuff.
     
  7. Timbox

    Timbox Well-Known Member

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    Got the battery in the mail and installed. Went to start it and nothing. Then I remembered that the white wire in the above pic was a ground for the harness. Did a little more wire work and all is good. I have an offer on ebay for a tank. The one I have is past recovers. Rusted through on the sides and front. Not just a little bit either, I tried to clean it up to see if I could braze it, nope, I would never trust it. That and I am sure the metal is so thin from rust that it would just break my heart once I got is filled with fuel.

    I tried to save a B65 Saber tank once, pinholes started to form again, so best to go with a good or better tank.

    Have a GPS speedo I am thinking of using. I will remove the guts from the interment cluster and then find a way to use the OEM panel to make a mount.

    On a side note, my family up in the UP of MI found out that I work on older bikes as a hobby. I now have a 1971 Honda Trail 90 on one of my tables. Lots of parts missing, but once I got the carb cleaned and hooked up the AUX fuel, she is running. Not to sure it is worth getting all the parts for and making it street legal again. I know the owner wants it for pure nostalgic value.
     
  8. Timbox

    Timbox Well-Known Member

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    New used seat is here. I also got a okay used tank from ebay. That has evaporust in it now, will give it a few days in this heat. The tank will need paint as it is really sun bleached, but in okay shape. A few small dents but compared to the tank I had with three large holes in it, I am happy.

    Need to take the time to get the GPS speedo mounted and powered. I should be able to make a mount from the original OEM gauge housing, that way it will be covered up with the mini screen.
     
  9. Timbox

    Timbox Well-Known Member

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    Got to take the bike around the field the first time. Well, it would not spin up under load. The brakes were sticking and lots of other little things but I think I found out why.
    [​IMG]GPZ timing by Tim Brown, on Flickr

    I can't believe that the bike even ran! I don't think I have ever seen timing pickup and advancer in that bad of shape. I have it soaking in Blaster and hope that I can get it working again. Wow.

    Broke the beads down on both tires and cleaned them out (Thanks Joe). Tires were leaking bad from getting dirt around the bead of the tires. The tires are okay to good, wanted to keep them. Working on the brakes to get them to release better. I was surprised the pucks are in good shape. I will have to work them a bit to get them to where I want them to be. Still just plugging away when I have the time.
     
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  10. Dave in Ireland

    Dave in Ireland Well-Known Member

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    That's the worst I've seen. Possibly been run in salt water, antics on the beach.
    In fact, come to think of it, I think a couple of my I 4 engines lack the paper gasket under the timing cover, as a lot of people - POs - think it doesn't matter.
    Surprising too, how much cruddy salty water can get into places without going to the beach - just a few winters on salted roads can cause havoc.
     
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  11. Timbox

    Timbox Well-Known Member

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    Took a lot of TLC, hammer and a punch to get that timing plate to move and then off. Cleaned it up with multiple things. Gave the timing advancer a good penetrating oil bath, dried up the area and put it back together. And just like that the bike runs so much better. I wonder why? lol
     
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  12. Timbox

    Timbox Well-Known Member

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    I thought I had better put a pic of that timing advancer on here to, just so you can see how nasty it was. [​IMG]Timing by Tim Brown, on Flickr
     
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  13. Timbox

    Timbox Well-Known Member

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    Having a hell of a time trying to find the right oil cooler for this bike. The one that came off the bike is red and has protruding. I have a black on that has the opposite connector. Don't know if I should keep looking for the right one on ebay or just get a whole new system (used) from ebay?

    Red one is the connector type I need.
    [​IMG]Cooler by Tim Brown, on Flickr
    [​IMG]Cooler 1 by Tim Brown, on Flickr
    Reason I need it, one side of the oil cooler is leaking badly and I don't think you can fix them.
     
  14. Huntchuks

    Huntchuks Well-Known Member

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    Unscrew the fitting from one and replace the other with it?
     
  15. Timbox

    Timbox Well-Known Member

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    @Huntchuks , I would love to do that, but these are secure and part of the whole unit. Looks like Kaw changed from yr to yr and model with this same type oil cooler. Always something. lol
     
  16. Dave in Ireland

    Dave in Ireland Well-Known Member

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    You could use a dash/6 (or whatever) converter. Nip into your nearest hydraulics stockist, and they'll sort you out.
     
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