1983 Kawasaki GPZ 550


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Coopacoopacoopa said:
I feel like you might already know this, but if there isn't a conversion bearing option you might be able to go the route of pressing the gpz steering stem in zx10r lower triple tree. My kz750r1 is using a zx9r upper and lower yokes with a kz steering stem. If the zx10r steering stem is smaller than the gpz stem, you're in business. Vice versa with those dimensions would make things a little trickier.

I might just call up allballs and give them the dimensions. The other option is just keeping them for another project that may be coming down in the works. The forks are now entirely rebuilt, and I'm about to embark on sealing the air assist off as I fitted progressive springs and no longer need them. I'm just going to thread the hole and epoxy a screw into place.

so here's an update...

the car fired
I had the plugs out and it sparked!
so the starter works, the wiring works, and I just need to clean everything up now. This is SO EXCITING MY BIKE WILL BE READY FOR SPRING!


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another quick video of some recent build stuff...
I've got tons of photos and only a few videos of build stuff day by day. I tend to work in bursts when I feel creative or angry and frustrated with something else in life.


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It started!


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Lots of work this week since I'm on vacation. Let's start with where we are so far:

Rear frame was repaired after bad chop job and hooped with the metal hoop kit from DCC and welding from Interstellar motor's Rich Odlum (on his new TIG machine)
seat pan fabbed out of steel
tank cleaning effort failed, too many holes in the factory one and I hated the look. Swapped for an 81 KZ550/GPZ550 tank. Eventually wouldn't mind getting the zx550 tank with the fuel gauge It fits great, but it's shorter so the seat itself needs to be extended

Replaced rear shock with YSS custom sprung unit
Tore down front forks, drilled damper rods and installed adjustable cartridge from YSS set to 7 turns on both sides
Air assist delete: 2 grub screws, tap and thread the holes, and use marine JB WELD around the sides of the screws to seal it up good
Progressive front spring kit, new fluid and seals

harness from scratch using M Unit as the base. It was totally overwhelming so I started with the ACC circuit, and then did the ignition circuit separately and it was much easier. Now I'm struggling through wiring up a gauge cluster.

It fires up and runs now, I rode it around the parking lot. Good time!



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This is looking great man!

What gaiters did you use? Put the wrong size on there and can't seem to find the right ones.

Painting the wheels looks good - I need to get that done!


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did a video blog update for this most recent buildup plus a sort of explanation of everything done so far...



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been up to a LOT lately. My better half is out of town helping her mom move up here so I've been left to my own devices. I'm also working night shifts so when I can't sleep from swapping back to the occasional day shift in the emergency room, I just go to the shop and bang out some wiring work.

Step 1: the M unit's M-LOCK key stopped working. No explanation from me as to why. It just suddenly stopped working. The master key still works and the LED lights up but no dice on anything else. i tried taking apart the broken slave key and re connecting the wires to the RFID chip but also no dice. The RFID chip inside is dead. :( I did make a custom aluminum key fob to transplant the guys into but to no avail. oh well.

The wiring was a bit of a mess before on the "wiring platter" I've created to house it (no room for a tucked frame box because of the monoshock linkage)
the wiring for the ignition wasn't done here, so imagine two more looms of wiring.

Here is what I came up with. Notice I've hidden wires for the M unit a little bit better, and I'm not running them underneath exposed to weather (this bike needs to be sort of reliable as it's my only motorcycle other than my 50cc scooter)

The main problem was that the ignition coils wiring was really bulks and in the way and awkward. Where the hell was I gonna put it so the wires were clean and not seen. It was about then after staring at it that it hit me after seeing guys on here doing this:

RUN THE WIRES IN THE FRAME. DONE. Managed to fish the wires through a tiny hole and install a nice skinny grommet. Everything is so much cleaner and the coil wires snake up easily into the seat pan without taking up one of the sides.

You'll notice above I'm using POSI TAP and POSI LOCK connectors. If you don't have these GET SOME. I swear they are amazing I first used them on my triumph tiger from a kit by EASTERNBEAVER for adding heated grips and they meet all the important mechanical standards. No solder but strong as hell and reversible if you need to do service and the wires need to come apart.


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So my next question: BROKEN M LOCK

I just need a new fob but I can't get ahold of revival cycles. I'm considering switching to a low tech key ignition. Anyone know a good one? Dime city cycles? It has to play nice with hte M UNIT. I also don't know how to wire up an M Unit

can anyone help with a diagram or something for me? I'm really considering ditching the M-LOCK as cool as it is...


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okay...new video of what I've been up to:

1. I built a new battery box I had to work around the fact that the tire was going to hit the seat pan if I wanted to use the full travel of my fancy shock (I'm tracking this thing, so yes I want to use the full travel)

2. The gauges are too big:

as much as I love the fancy big gauges, I think they're too large and detract from the bike. They also run their wiring right into the darn headlight. Stupid wires! Only so many places I can hide them! Wiring is an art and I'm way too type A to leave them mucking about!
What gauges do y'all run?
Thinking of running another ACEWELL

Or some white gauges from DCC, except their speedometers are all KPH and their tachometers are all cable driven not electronic.

3. the gosh darn mother flipping seat pan:
you can see now that the battery and electronics box takes up space where I want to be sitting. How can I cleverly craft a seat pan that COVERS the battery box without crushing it. I'm going to have to have it rest on the seat rails somehow, and then click into place because things that click into place make me happy. Anyone got any ideas? HALP ME VINTAGE BIKE PEOPLE?

This bike was way more of a mess than i expected, but I'm happy with the direction it's going.

did I mention I tuned up the carbs? She runs beautifully now! I just want to RIDE!


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and it runs. It's not done, but I took it for a ride. The idle needs tuning. I'm pretty certain it's running rich as heck since I've got pods and stock exhaust. I've got a MOTAD exhaust coming in the mail at some point, I ditched the MAC.



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Well, the DGR 2018 came and went. The bike ran great, but it's time to take it apart again and do some powdercoating, detab the frame, and maybe swap to a rounded tank from the KZ550 LTD? it's been a fun year, but winter is when the real fun happens and the bike will be undergoing even more change and some bearings will be refreshed!

and finally in this pic everyone tells me I look like Adrien Brody. heh.


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alright! It's been a long winter/year. I haven't been in the shop as doclife has taken over a lot and I've also been trying to get back in physical shape. I gained WAY too much weight last year and none of my clothes fit! I'm back down to fighting weight, so time to dig into this thing again!

SO... I ripped the engine out. The frame needed to be de-tabbed (all the fairing tabs I'm not using) and the tail light needs a recessed housing. I got it done!
Now the big barrier is that the engine was at one point spray painted with a thin layer of flat black paint. It looks really bad up close. I want that layer off. I wouldn't mind repainting it gloss black (way easier to keep clean) or just keeping it silver. I've polished the stator points and sprocket covers for contrast and gotten the fins polished from where the casting was really rough. ANYWAY here's pics:



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well, i've been hard at work. I sold my VTR1000F and have been dumping all my time into wrenching. Carbs still having leaks but now from cyl 3 and only when it gets hot (goes through overflow) and that may explain why cyl 3 and 4 are running a little richer (dumping into 3 and overflow some into 4) find out the float needle seat there is old and needs replacing too, so I go for it. hopefully we're set now.

I stripped the tank recently. here are some noteworthy pictures

finished internally running the ignition wiring. that was fun.

Got the Motad exhaust installed. Traded a young dude my MAC because the Motad was too quiet for him.

you can see the mockup of a potential paint scheme here with my bike in front of Rich the owner of Interstellar's CB750 he just sold.

comparing the original tank to the new one

easier to notice here how the link of the whole bike cleans up a lot with the more vintage tank

a little bit of my inspiration

stripped the tank and got off all the old rusty and dirty paint. tank is surprisingly in good shape. a few small dings but completely superficial and no rust. into the actual metal. even behind the emblems was clean.


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Back at it again. I'm completing my residency here in Rochester NY and bringing the bike with me to California. I've got quite a bit more work left to do, but I'll give a little update:
The List:
replacing the rear linkage with adjustable rod bearings so I can fine tune the height a little bit.
front fork flush, and re-adjust the YSS cartridge emulators so they ride a bit better for my weight
polish the triangular linkage piece so it looks nice, adn I just like polishing things
machine new flush mount fork top caps since I gutted the forks for modern internals and the air assist is gone and deleted.
new pads and rotors these are pretty old.

carbon deposits clean : priority. it looked BAD in there.
polish combustion chambers: prevents buildup slightly, and the head is open might as well.
valves: clean, replace any that look burnt or worn, and replace the valve seals (guides if they seem bad) and give them a proper lapping
give the carbs a once over again just to be sure.
put a tap and hose on the crank case vent so the hose doesn't keep popping off.
fit the old yoshimura pipe. it's a bit bangd up and needs resto and re packing.
fit new earls' oil cooler. i know the stocker is fine, but all the cool kids are doing it.

XDone (needs to be adjusted) rearsets from Tarozzi install:
paint tank (black? red? probably black)
fender: trimmed, shaped, strip paint and repaint black with epoxy so it's durable.
re-do the seat pan so the battery isn't flopping around and the R/R isn't just hanging by a thread in the wind.
black anodize (or tint) the polished bits on the engine, etch the shop logo into the points cover.

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