Author Topic: Dr Cat Rides Again! 83 gpz550 resurrection project  (Read 1038 times)

Offline doctorcat

  • Posts: 43
Dr Cat Rides Again! 83 gpz550 resurrection project
« on: Aug 14, 2017, 21:09:43 »
Hi all.
Transplant from california to upstate NY.
Came into this bike when we rented our house. It was sitting in the garage, in need of some love.
I got the house owner to sell the bike for cheapie, and it was in pretty decent condition all around.
It had been chopped up a bit by a few folks trying to make it less plastic clad. It's not a bad idea, as the frame on these bikes was quite pretty and showing it off is great.

here she is when I first got her, 1983 Kawasaki GPZ550

now the other side...maybe you can see that brownish gunk on the top of the tank? That was rust eating through from inside the tank to the outside

I took the tank to a shop to see if they could weld it, but it was far too rusted. There was a hole in the roof and water and snow just dripped away eating the insides and out (gas cap wasn't sealing up right) The shop was interstellar motors, here in ROC, NY. Great bunch of guys!

I looked for another tank, but to be honest I hated the shape of the stock tank. The lines were wrong on the bike. I noticed a member on here JFarhanbod had done up a GPZ550 really nicely (his is an 84) and he fit the 81 style tank on his.

I had to grind off the tabs for my ignition coils and make a bracket to relocate them, but the tank fit great!

Forgot to mention, the wiring was a mess. Lots of corrosion, lots of stripped wiring that when I drove the bike around at first, it sparked and sputtered. I decided enough was enough, and removed the harness.

I picked up an M-unit and some buttons, plus a domino throttle...

while I wait for those to show up, I started to ponder the seat pan:
I need somewhere to stash a battery, and the electronics.
I also need to mount up a seat somehow, and not the awkwardly shaped stock seat.

I want to have SOME room for storage, so a rear hump is in order (though maybe the battery will eat all that space up.)

Here is the template for the seat I've measured several times and tried a few layups... I had interstellar motors (shameless plug for them again i guess? GREAT shop) weld up the rear frame hoop.

now for the ideas about making an undertray: looks like there isn't much clearance towards the rear of the bike with the tire. I can't follow the triangular plates on the frame where the dual shocks used to mount on the prev year model.
(although I think it would look better this way...)

and then up towards the front, where the factory ignition, and regulator rectifier mounted? Not a bad spot, but totally exposed to the elements.
maybe you can't quite see it, but this is a UNITRAC model suspension and the suspension linkage takes up a lot of that middle area. There's still a teeny bit of space, though. I could probably squeeze an electrics box in there, but I wouldnt fit the M unit I don't think, and I wouldn't want the M unit right next to a boiling hot regulator rectifier.

And then there's the issue of the seat shape: It's going to need to be a taller seat height (a low brat seat makes the bike too small for me)

so I got the idea to build the seat base like earlier, and maybe have that be the electronics tray. Electronics on TOP of the frame rails.
Then somehow build the seat on top of the electronics, and somehow have it swivel or click open so I can take a look at the electronics, and maybe have some storage space in a cafe hump for my gloves when I'm not riding.

well, that's all for now. I'm kind of stuck at an impasse. I don't know what to do next, frozen in indecision.
Where do I stash the electronics and battery?
How do I build a seat over this with a good shape, or get a seat pan build that wont crack when I sit on it.
Do I have the seat pan have a little lip to cover the frame up, or do I have it like pictured just sitting on top of the rails?

little details, and I'm still not sure if I know which one is best.

Thanks for watching/reading!

Offline Raab242

  • Posts: 42
Re: Dr Cat Rides Again! 83 gpz550 resurrection project
« Reply #1 on: Aug 15, 2017, 09:24:06 »
Looks good! That tank works so much better I think

Sent from my LG-K425 using DO THE TON mobile app

Offline The Jimbonaut

  • *
  • Posts: 1225
    • Lost Apostle
Re: Dr Cat Rides Again! 83 gpz550 resurrection project
« Reply #2 on: Aug 15, 2017, 11:26:12 »
Welcome mate from Montreal, man your ride is shaping up nicely.  I really dig the original tank (maybe because it looks like the tank on my '81 CB750) but the replacement tank is a great fit too.

I made my seat pan from galvanized steel (you can see the steps in my Montreal Manchild thread in the Introductions forum here) - can't remember exactly but think it was either 16 or 18 gauge.  This made it relatively easy to cut (only had a dremel which meant it took a while - a grinder with a cutting disk would get through it in no time) and filed the edges nice and smooth.  Made mine so that it sat directly on top of the rails - looking down from above it sat maybe 2 or 3mm inset from the outside edges of the rails.  That way, once the seat was foamed and upholstered, there was no overlap.  It's strong - mine bolts into a strip of steel I welded across the frame near the seat hoop, and I made a small tab which I riveted on the the front of the pan which secures the seat into the stock mounting bracket near the tank.

Looking forward to seeing how your bike shapes up, have fun mate!
"I'm telling you Donnie, nuthin' but nuthin' but right"

Offline doctorcat

  • Posts: 43
Re: Dr Cat Rides Again! 83 gpz550 resurrection project
« Reply #3 on: Aug 18, 2017, 14:49:13 »
I think I'm going to do a café racer seat hump. I need a place to store a battery (and gloves would be nice too...) and a brat seat might not clear the suspension travel anyway. I know JFarhanbod on here has a SICK GPZ550 Brat (his is an 84 and I found him on Instagram and got some help from him!) and I don't wanna jock his style. His bike is wicked cool!

I can't afford the GSXR or 636 front end swap right now since Ijust moved and I'm buying tools (welder!) so the prev owner left me a suspension rebuild kit for the forks (progressive springs, new seals, fork oil) so I'll rock that for this season. This winter I'm tearing down and powdercoating the framey bits.

My hard and fast goal is to finish/get it running by Sep 24th which is Rochester, NY's Distinguished Gentleman's Ride.

I'll keep you fine folks updated as I keep building. Is there a proper forum for a build thread?

Offline doctorcat

  • Posts: 43
Re: Dr Cat Rides Again! 83 gpz550 resurrection project
« Reply #4 on: Sep 10, 2017, 20:06:33 »
quick update:
The bike has been moved into interstellar motors shop where I'm continuing to do some more work on it. I got a seat pan layout made of a sheet of steel.
I ran into a problem though. You can see that the tank mount is kind of tough to clear. I have to figure some way to get the seat pan to cover that bit. I have at my disposal a sheet metal bender, but I can't quite get a tiny little right angle as the minimum length between bends is about 2 inches. Somehow I've got to make another mounting point for the seat pan on the factory tank mount, so I think I have to curve the metal around it? Gonna take some creativity, I'm thinking. I'm kinda stuck right now.

I cant get around that piece. I ended up cutting off the two side "wings" on the side and just terminating the pan at the tank mounting hump.

underside view of the pan. I still need to somehow attach some mounts to the frame so I can screw it down.

Offline doctorcat

  • Posts: 43
Re: Dr Cat Rides Again! 83 gpz550 resurrection project
« Reply #5 on: Sep 10, 2017, 21:10:46 »
got into the carbs today too... eek.

glad I decided to check them. They were disgusting.

this bike definitely wont be ready in time for the DGR. I can't possibly finish before the 20th to get it even remotely running. I have to say I'm a bit disappointed in myself but it's just taking a lot longer than I thought it would. Every time I overturn another stone, the bike needs something else.

Offline diegoribba

  • Posts: 5
Re: Dr Cat Rides Again! 83 gpz550 resurrection project
« Reply #6 on: Sep 11, 2017, 14:30:19 »
don't lower  your arms! keep pushing! this could be a legendary built!

Offline doctorcat

  • Posts: 43
Re: Dr Cat Rides Again! 83 gpz550 resurrection project
« Reply #7 on: Sep 11, 2017, 22:51:11 »
figured this bit out. now I have to decide if I'm going to hammer the "wings" down on top for a narrowing of the saddle as it approaches the tank. Right now it pokes my legs because it's so sharp.

compare to yesterday

so I'm going to rivet the new piece down that I made with the metal bender. that thing is a godsend!

wider shot of the whole seat pan

circles on the green tape are where i'll drill and then place rivets to secure it. I still need to weld cross brackets for securing the seat pan onto the frame.

(gonna hammer the two wide sides down if I can so they dont poke my legs
Actually, I should stop calling it "seat pan" this is just the "undertray"

I'm ordering up a piece of KYDEX Thermoplastic which I will heat form around the metal tray. This will be what the foam and staples for the fabric go onto. I'm going to have a layer of hard foam (like yoga mat material) and then a layer of softer foam on top (maybe even some GEL like from those purple mattresses. I think I have a square of it sitting at home...) I want the seat to have a rounder profile since I've got a narrow arse.

KYDEX is what Gun enthusiasts like to use to make conceal carry holsters. I may be a Californian, but I was raised in Texas and I know a thing or two about firearms!  Has anyone here used KYDEX for making a saddle before? It seems to be a good base if it is thick enough?

oh and I'm trying some shapes for a seat hump. I need less space than I thought originally. Going to use a shorai battery. I have two mounting options: 1: use the stock location for a full size shorai, or 2: use the seat hump for a mini shorai.

here's the seat hump design in progress. I may want to make it larger/taller?

right now it's set up to be a solo seat so it's "in line" with the frame tubing. I could push it back further and allow for a passenger... Gotta have the hump though nowhere else to store the electrics! The monoshock takes up all the room.

Carbs are drying, but will need some more cleaning to get all the scale and muck off. That's another project for another day. I had a hell of a time getting the order of operations right to get the metal bent.

okay. signing off. I should have taken a shot of mocking up the electricals, but I'll snap a photo of it tomorrow

Offline doctorcat

  • Posts: 43
Re: Dr Cat Rides Again! 83 gpz550 resurrection project
« Reply #8 on: Sep 13, 2017, 20:12:24 »
today was filled with lots of hammering.

things that I did:

Put on new footpegs. The old ones were boat anchors, and I had a pair of CBR600 F4i pegs that I really liked (I was riding my friend's F4i for a couple months after I had sold my Tiger touring rig before moving to upstate NY) and they were just brand new spares sitting around my basement.

then I hammered the living @#$% out of the seat pan to get it to have a nice curve for my legs to rest on. It's not perfectly symmetrical, but it's the best that I could do. The damn steel is really hard, and even with heat it was a bloody murder to get a nice bend out of it. The good news is that now it fits nicely and my legs don't get poked and I can get right up on the tank like I like to do. I'm gonna need some tank grips!!!

Then I cut a hold for the tank to mount to the frame at the rear. The actual seat cushion will sit on top of the tank mount and hopefully the plastic will form around it and let me get a nice cushy base to work with.

Then I went to the hardware store and got myself a rivet gun. My welder friend here from Interstellar Motors is busy getting ready for the Distinguished Gentleman's Ride

(so am I. I work in mental health and the added topic this year is the disproportionately high male suicide rate, something that strikes me particularly hard. I lost a friend whom I worked on motos, bicycle racing, and through a really rough time with, to a firearm suicide a year ago.) I'm doing this for him, and he's part of the reason I decided to become the type of doctor I did.

anyway, onto today's work.

you can't really see the places I hammered it down, but the seat foam is on there now. I think I need to glue it together. Honestly...for the DGR It's probably gonna be wrapped in a mexican blanket =) Don't have time to upholster it all fancy.
you can see the gigantor ugly footpegs are gone replaced by nice alloy factory HONDA pegs (honda fanboyism kicking in.) they are spring loaded and I used the factory GPZ bolts and cotter pins to get them in there.

next bit (the easy part I guess) I got the new gauge mounted up. I went for a center mount, though I think an offset mount may work better (and I can have a temp/voltage gauge next to it)
I'll have to lose the mechanical speedometer I think, but the bike has provisions for a new sensor mount and I have a spot on the forks to mount it so no big deal I can use the magnetic sensor instead.
I was actually thinking of having the big guage on the right, and a phone mount on the left for GPS. anyway, not important right now since it doesn't need that to get running.

oh, and I registered the bike today. I have 10 days to get it inspected (i.e. running) and the DGR is in 2 weeks. I may have to enlist the help of the interstellar motors crew to get the M Unit running on the bike.

oh. speaking of which, I got all that crap mocked up, and I have a carbon fiber layup kit to make the seat cowl. I just need to know how much space I'm going to need. I have wire loom, heat shrink tubing, and some connectors en route. next step is bending a bracket for the coils and getting the wires set.

explanation: the battery is actually smaller. that's my triumph tiger's battery (I'll be buying another of those come this spring for some touring rides, either that or another project XS1100 for 2up riding...)
the R/R and ignition box are going to be mounted UNDER the seat pan for cooling's sake (where they were in the factory locations.

now if only I had a friend I could pay to do the wiring for me =( or at least the damn diagram. I don't do wires: It's the reason I hated neurosurgery. It's like one gigantic human wiring loom and it makes me want to scream. It takes a special kind of nutter to...
well, my uncle is a neurosurgeon so I guess I shouldn't say anymore.  ;)

oh. btw. the rear caliper is frozen. So now another to do:
1. Clean carbs, and reinstall.
2. rear brake soak in pine sol, flush, install stainless lines and reinstall on bike.
3. WIRE UP THE DAMN BIKE. (I keep putting this off because I keep having ACTUAL nightmares about it) hump build to cover electronics.
5. Ride it!

once the DGR is over
6. Fork seals and springs (which came with the bike in separate boxes) OR do that GSXR front end conversion I'm lusting after on EBAY. (adios paycheck!)
7. Paint the tank White with gold metallic flake
8. Exhaust, headers, and stage 3 jet kit.

It's happening!!!!! So nice to see it actually coming together and looking like a proper bike now.

also, I'm off to Chicago tonight for RIOT FEST (punk rock festival) so if anyone from DTT is in CHI-TOWN, let me know and we can meet up for a brew.

Offline diegoribba

  • Posts: 5
Re: Dr Cat Rides Again! 83 gpz550 resurrection project
« Reply #9 on: Sep 14, 2017, 16:58:50 »
WIRE UP THE DAMN BIKE. (I keep putting this off because I keep having ACTUAL nightmares about it)

as the human "wiring", a motorcycle wiring have sub-systems. you better start with the ignition and then go to lightning.
i absolutely recommend doing a schematic if you plan to do a custom wiring, since it's the best way to troubleshoot when problems come. it will also help to have a relaxed approach to wiring, since after making a diagram, you will be very aware of how, why and where place every inch of wire.
remember to do one thing at a time... just make sure you keep moving forward!

Offline doctorcat

  • Posts: 43
Re: Dr Cat Rides Again! 83 gpz550 resurrection project
« Reply #10 on: Sep 20, 2017, 14:17:04 »
so I'm still having trouble, and hear me out.

I can't understand the FUNCTION of the wires as I'm trying to re-wire the bike for the M-Unit. I'm trying to plumb the Regulator/Rectifier (Easy enough, the brown wire goes to an auxiliary/switched power wire) and then the ignition box.

The ignition box seems to be the problem. Two sets of wires. Blue/black, Red/Yellow: okay these go to the coil pickups

now theres yellow/black, blue, dark green, Red/Yellow: these go to the ignition coils?
blue gets tapped to the tachometer?

yellow black goes to ground? I don't actually know. I'm just guessing from these two diagrams...

CB750 diagram I'm trying to emulate:

and what I have come up with so far: